CHAPTER X.. At the White House, Greenwich. From His Resignation

AT THE WHITE HOUSE, GREENWICH. FROM HIS RESIGNATION OF OFFICE ON AUGUST 15TH, 1881, TO HIS DEATH ON JANUARY 2ND, 1892.

HISTORY OF HIS LIFE AFTER HIS RESIGNATION OF OFFICE.

On the 16th of August 1881 Airy left the Observatory which had been his residence for nearly 46 years, and removed to the White House. Whatever his feelings may have been at the severing of his old associations he carefully kept them to himself, and entered upon his new life with the cheerful composure and steadiness of temper which he possessed in a remarkable degree. He was now more than 80 years old, and the cares of office had begun to weigh heavily upon him: the long-continued drag of the Transit of Venus work had wearied him, and he was anxious to carry on and if possible complete his Numerical Lunar Theory, the great work which for some years had occupied much of his time and attention. His mental powers were still vigorous, and his energy but little impaired: his strong constitution, his regular habits of life, the systematic relief which he obtained by short holiday expeditions whenever he found himself worn with work, and his keen interest in history, poetry, classics, antiquities, engineering, and other subjects not immediately connected with his profession, had combined to produce this result. And in leaving office, he had no idea of leaving off work; his resignation of office merely meant for him a change of work. It is needless to say that his interest in the welfare and progress of the Observatory was as keen as ever; his advice was always at the service of his successor, and his appointment as Visitor a year or two after his resignation gave him an official position with regard to the Observatory which he much valued. The White House, which was to be his home for the rest of his life, is just outside one of the upper gates of the Park, and about a quarter of a mile from the Observatory. Here he resided with his two unmarried daughters. The house suited him well and he was very comfortable there: he preferred to live in the neighbourhood with which he was so familiar and in which he was so well known, rather than to remove to a distance. His daily habits of life were but little altered: he worked steadily as formerly, took his daily walk on Blackheath, made frequent visits to Playford, and occasional expeditions to the Cumberland Lakes and elsewhere.

The work to which he chiefly devoted himself in his retirement was the completion of his Numerical Lunar Theory. This was a vast work, involving the subtlest considerations of principle, very long and elaborate mathematical investigations of a high order, and an enormous amount of arithmetical computation. The issue of it was unfortunate: he concluded that there was an error in some of the early work, which vitiated the results obtained: and although the whole process was published, and was left in such a state that it would be a comparatively simple task for a future astronomer to correct and complete it, yet it was not permitted to the original author of it to do this. To avoid the necessity of frequent reference to this work in the history of Airy's remaining years, it will be convenient to summarize it here. It was commenced in 1872: "On Feb. 23rd in this year I first (privately) formed the notion of preparing a Numerical Lunar Theory by substituting Delaunay's numbers in the proper Equations and seeing what would come of it." From this time forward till his power to continue it absolutely failed, he pursued the subject with his usual tenacity of purpose. During his tenure of office every available opportunity was seized for making progress with his Lunar Theory, and in every Report to the Visitors a careful statement was inserted of the state in which it then stood. And, after his resignation of office, it formed the bulk of his occupation. In 1873 the Theory was formed, and by 1874 it was so far advanced that he published in the Monthly Notices of the Royal Astronomical Society a statement of the fundamental points of the Theory. In 1875, the Theory having advanced to a stage where extensive arithmetical computation was required, he obtained a small grant from the Government in aid of the expense of the work, and other grants were made in subsequent years. By 1878 the calculations were so far advanced that an opinion could be formed as to the probable accuracy of the Theory, and the following remark is made: "A cursory collation of the terms relating to the Areas (in the Ecliptic) led me to suppose that there might be some error in the computations of the Annual Equation and related terms;" but no error could be discovered and the work proceeded. The complex character of the Theory, and the extreme care required in the mathematical processes, are well illustrated by the following statement, which occurs in the Report of 1879, "An important error in the theoretical formulae for Variations of Radius Vector, Longitude, and Latitude, was discovered; some calculations depending on them are cancelled." In 1880 and 1881 the work was continued, but was "sadly interrupted by the pressure of the Transit of Venus work and other business." After his resignation of the Office of Astronomer Royal he had no further public assistance, and did much of the computations himself, but a sum of £100 was contributed by Mr De La Rue in furtherance of the work, and this sum was spent on computers. In his retirement the work made good progress, and on Dec. 31st, 1882, he made the following note: "I finished and put in general order the final tables of Equations of Variations. This is a definite point in the Lunar Theory.... I hope shortly to take up severely the numerical operations of the Lunar Theory from the very beginning." The work was continued steadily through 1883, and on Mar. 24th, 1884, he made application through the Board of Visitors to the Admiralty to print the work: after the usual enquiries as to the expense this was acceded to, and copy was sent to the printers as soon as it was ready. The first printed proofs were received on Feb. 5th, 1885, and the whole book was printed by the end of 1886. From the frequent references in his journal to errors discovered and corrected during the progress of these calculations, it would seem likely that his powers were not what they had been, and that there was a probability that some important errors might escape correction. He was far too honest to blind himself to this possibility, and in the Preface to his Numerical Lunar Theory he says thus: "I have explained above that the principle of operations was, to arrange the fundamental mechanical equations in a form suited for the investigations of Lunar Theory; to substitute in the terms of these equations the numerical values furnished by Delaunay's great work; and to examine whether the equations are thereby satisfied. With painful alarm, I find that they are not satisfied; and that the discordance, or failure of satisfying the equations, is large. The critical trial depends on the great mass of computations in Section II. These have been made in duplicate, with all the care for accuracy that anxiety could supply. Still I cannot but fear that the error which is the source of discordance must be on my part. I cannot conjecture whether I may be able to examine sufficiently into this matter." He resolutely took in hand the revision of his work, and continued it till October 1888. But it is clear from the entries in his journal that his powers were now unequal to the task, and although from time to time he suspected that he had discovered errors, yet it does not appear that he determined anything with certainty. He never doubted that there were important errors in the work, and later on he left the following private note on the subject:

NUMERICAL LUNAR THEORY.

1890, Sept. 29.

I had made considerable advance (under official difficulties) in calculations on my favourite Numerical Lunar Theory, when I discovered that, under the heavy pressure of unusual matters (two Transits of Venus and some eclipses) I had committed a grievous error in the first stage of giving numerical value to my Theory.

My spirit in the work was broken, and I have never heartily proceeded with it since.

G.B. AIRY.

Probably the error referred to here is the suspected error mentioned above in his Report of 1878, as to which he subsequently became more certain.

Whatever may be the imperfections of the Numerical Lunar Theory, it is a wonderful work to have been turned out by a man 85 years old. In its idea and inception it embodies the experience of a long life actively spent in practical science. And it may be that it will yet fulfil the objects of its author, and that some younger astronomer may take it up, correct its errors (wherever they may be), and fit it for practical use. And then the labour bestowed upon it will not have been in vain.

Subject always to the absorbing occupations of the Lunar Theory he amused himself with reading his favourite subjects of History and Antiquities. His movements during the remainder of the year 1881 were as follows: In September he paid a two days' visit to Lady Herschel at Hawkhurst. From Oct. 4th to 17th he was at the Cumberland Lakes and engaged in expeditions in the neighbourhood. From Nov. 5th to 8th he was at Cambridge, inspecting Prof. Stuart's workshops, and other scientific institutions. On Dec. 13th he went to Playford.--Amongst miscellaneous matters: in November he wrote to Mr Rothery on the loss of the 'Teuton' at some length, with suggestions for the safer construction of such vessels.--In October he was asked for suggestions regarding the establishment of a "Standard Time" applicable to the railway traffic in the United States: he replied as follows:

1881, Oct. 31.

SIR,

I have to acknowledge your letter of October 17, introducing to my notice the difficulty which appears to be arising in America regarding a "Standard Time," for extensive use throughout N. America "applicable to railway traffic only." The subject, as including considerations of convenience in all the matters to which it applies, is one of difficulties probably insuperable. The certainty, however, that objections may be raised to every scheme, renders me less timid in offering my own remarks; which are much at your service.

I first comment upon your expression of "Standard Time... applicable to railway traffic only." But do you mean this as affecting the transactions between one railway and another railway, or as affecting each railway and the local interests (temporal and others) of the towns which it touches? The difference is so great that I should be disposed to adopt it as marking very strongly the difference to be made between the practices of railways among themselves and the practices of railways towards the public; and will base a system on that difference.

As regards the practices of railways among themselves: if the various railways of America are joined and inosculated as they are in England, it appears to me indispensable that they have one common standard among themselves: say Washington Observatory time. But this is only needed for the office-transactions between the railways; it may be kept perfectly private; never communicated to the public at all. And I should recommend this as the first step.

There will then be no difficulty in deducing, from these private Washington times, the accurate local times at those stations (whose longitude is supposed to be fairly well known, as a sailor with a sextant can determine one in a few hours) which the railway authorities may deem worthy of that honour; generally the termini of railways. Thus we shall have a series of bases of local time, of authoritative character, through the country.

Of such bases we have two, Greenwich and Dublin: and they are separated by a sea-voyage. In the U.S. of America there must be a greater number, and probably not so well separated. Still it is indispensable to adopt such a system of local centers.

No people in this world can be induced to use a reckoning which does not depend clearly upon the sun. In all civilized countries it depends (approximately) on the sun's meridian passage. Even the sailor on mid-ocean refers to that phenomenon. And the solar passage, with reasonable allowance, 20m. or 30m. one way or another, must be recognized in all time-arrangements as giving the fundamental time. The only practical way of doing this is, to adopt for a whole region the fundamental time of a center of that region.

And to this fundamental time, the local time of the railway, as now entering into all the concerns of life, must be adapted. A solicitor has an appointment to meet a client by railway; a physician to a consultation. How is this to be kept if the railway uses one time and every other act of life another?

There is one chain of circumstances which is almost peculiar--that of the line from New York to San Francisco. Here I would have two clocks at every station: those on the north side all shewing San Francisco time, and those on the south all shewing New York time. Every traveller's watch would then be available to the end of his journey.

A system, fundamentally such as I have sketched, would give little trouble, and may I think be adopted with advantage.

I am, Sir, Your faithful servant, G.B. AIRY.

Mr Edward Barrington.

1882

He returned from Playford on Jan. 17: his other movements during the year were as follows: from Apr. 27th to May 11th he was at Playford; and again from August 1st to 24th. From Oct. 9th to Nov. 1st he was travelling with his two unmarried daughters in the Lake District of Cumberland: the journey was by Furness and Coniston to Portinscale near Keswick; on Oct. 13th he fell and sprained his ankle, and his excursions for the rest of the time were mainly conducted by driving. Shortly after his return, on Nov. 11th, while walking alone on Blackheath, he was seized with a violent attack of illness, and lay helpless for some time before he was found and brought home: he seems however to have recovered to a great extent in the course of a day or two, and continued his Lunar Theory and other work as before. On June 22nd he made the following sad note, "This morning, died after a most painful illness my much-loved daughter-in-law, Anna Airy, daughter of Professor Listing of Göttingen, wife of my eldest son Wilfrid." In February he wrote out his reminiscences of the village of Playford during his boyhood.

In June he was much disturbed in mind on hearing of some important alterations made by the Astronomer Royal in the Collimators of the Transit Circle, and some correspondence ensued on the subject.--During the year he had much correspondence on the subject of the subsidences on Blackheath.

The following letter was written in reply to a gentleman who had asked whether it could be ascertained by calculation how long it is since the Glacial Period existed:

1882, July 4.

SIR,

I should have much pleasure in fully answering your questions of July 3 if I were able to do so: but the subject really is very obscure.

(1) Though it is recognized that the glacial period (or periods) is late, I do not think that any one has ventured to fix upon a rude number of years since elapsed.

(2) We have no reason to think that the mean distance of the earth from the sun has sensibly altered. There have been changes in the eccentricity of the orbit (making the earth's distance from the sun less in one month and greater in the opposite month), but I do not perceive that this would explain glaciers.

(3) I consider it to be certain that the whole surface of the earth, at a very distant period, was very hot, that it has cooled gradually, and (theoretically and imperceptibly) is cooling still. The glaciers must be later than these hot times, and later than our last consolidated strata: but this is nearly all that I can say.

I am, Sir, Your obedient Servant, G.B. AIRY.

James Alston, Esq.

1883

From May 2nd to 29th he was at Playford. From July 10th to 20th he was travelling in South Wales with his daughters.--From Oct. 10th to Nov. 10th he was at Playford.--Between Nov. 20th of this year and Jan. 4th of the year 1884, he sat several times to Mr John Collier for his portrait: the picture was exhibited in the Academy of 1884; it is a most successful and excellent likeness.

Throughout the year he was very busy with the Numerical Lunar Theory.--In March he was officially asked to accept the office of Visitor of the Royal Observatory, which he accepted, and in this capacity attended at the Annual Visitation on June 2nd, and addressed a Memorandum to the Visitors on the progress of his Lunar Theory.--On March 12th he published in several newspapers a statement in opposition to the proposed Braithwaite and Buttermere Railway, which he considered would be injurious to the Lake District, in which he took so deep an interest.--In May he communicated to "The Observatory" a statement of his objections to a Theory advanced by Mr Stone (then President of the Royal Astronomical Society) to account for the recognized inequality in the Mean Motion of the Moon. This Theory, on a subject to which Airy had given his incessant attention for so many years, would naturally receive his careful attention and criticism, and it attracted much general notice at the time.--In December he wrote to the Secretary of the Royal Astronomical Society his opinion as to the award of the Medal of the Society. In this letter he stated the principles which guided him as follows: "I have always maintained that the award of the Medal ought to be guided mainly by the originality of communications: that one advance in a new direction ought in our decision to outweigh any mass of work in a routine already established: and that, in any case, scientific utility as distinguished from mere elegance is indispensable."--In July Lieut. Pinheiro of the Brazilian Navy called with an autograph letter of introduction from the Emperor of Brazil. The Lieutenant desired to make himself acquainted with the English system of Lighthouses and Meteorology, and Airy took much trouble in providing him with introductions through which he received every facility for the thorough accomplishment of his object.--On Oct. 8th he forwarded to Prof. Cayley proofs of Euclid's Propositions I. 47 and III. 35 with the following remarks: "I place on the other side the propositions which may be substituted (with knowledge of Euclid's VI. book) for the two celebrated propositions of the geometrical books. They leave on my mind no doubt whatever that they were invented as proofs by ratios, and that they were then violently expanded into cumbrous geometrical proofs."--On June 28th he declined to sign a memorial asking for the interment of Mr Spottiswoode in Westminster Abbey, stating as his reason, "I take it, that interment possessing such a public character is a public recognition of benefits, political, literary, or philosophical, whose effects will be great and durable. Now I doubt whether it can be stated that Mr Spottiswoode had conferred such benefits on Society. "But he adds at length his cordial recognition of Mr Spottiswoode's scientific services.--Throughout his life Airy was a regular attendant at church, and took much interest in the conduct of the Church services. In October of this year he wrote a long letter to the Vicar of Greenwich on various points, in which occurs the following paragraph: "But there is one matter in the present form of the Church Service, on which my feeling is very strong, namely the (so-called, I believe) Choral Service, in the Confession, the Prayer, and the Creed. I have long listened with veneration to our noble Liturgy, and I have always been struck with the deep personally religious feeling which pervades it, especially those parts of it which are for 'The People.' And an earnest Priest, earnestly pressing these parts by his vocal example on the notice of the People, can scarcely fail to excite a corresponding earnestness in them. All this is totally lost in the choral system. For a venerable persuasion there is substituted a rude irreverential confusion of voices; for an earnest acceptance of the form offered by the Priest there is substituted--in my feeling at least--a weary waiting for the end of an unmeaning form." He also objected much to singing the responses to the Commandments.

1884

From Apr. 29th to May 30th he was at Playford, concluding his Journal there with the note "So ends a pleasant Vacation."--On June 11th he went to Cambridge and attended the Trinity College Commemoration Service, and dined in Hall.--From Aug. 14th to Sept. 11th he was at Playford.--On Sept. 26th he made an expedition to Guildford and Farnham.--During this year he was closely engaged on the Numerical Lunar Theory, and for relaxation was reading theology and sundry books of the Old Testament.

On June 7th he attended at the Visitation of the Royal Observatory.--In a letter written in April to Lt.-Col. Marindin, R.A., on the subject of wind pressure there occurs the following remark: "When the heavy gusts come on, the wind is blowing in directions changing rapidly, but limited in extent. My conclusion is that in arches of small extent (as in the Tay Bridge) every thing must be calculated for full pressure; but in arches of large extent (as in the Forth Bridge) every thing may be calculated for small pressure. And for a suspension bridge the pressure is far less dangerous than for a stiff arch."--In January he had some correspondence with Professor Tyndall on the Theory of the "White Rainbow," and stated that he thoroughly agreed with Dr Young's explanation of this phaenomenon. --The following is extracted from a letter on May 1st to his old friend Otto Struve: "I received from you about 3 or 4 weeks past a sign of your friendly remembrance, a copy of your paper on the Annual Parallax of Aldebaran. It pleased me much. Especially I was delighted with your noble retention of the one equation whose result differed so sensibly from that of the other equations. It is quite possible, even probable, that the mean result is improved by it. I have known such instances. The first, which attracted much attention, was Capt. Kater's attempt to establish a scale of longitude in England by reciprocal observations of azimuth between Beachy Head and Dunnose. The result was evidently erroneous. But Colonel Colby, on examination of the original papers, found that some observations had been omitted, as suspicious; and that when these were included the mean agreed well with the scale of observation inferred from other methods."--In a letter to the Rev. R.C.M. Rouse, acknowledging the receipt of a geometrical book, there occurs the following paragraph: "I do not value Euclid's Elements as a super-excellent book of instruction--though some important points are better presented in it than in any other book of geometrical instruction that I have seen. But I value it as a book of strong and distinct reasoning, and of orderly succession of reasonings. I do not think that there is any book in the world which presents so distinctly the 'because...... therefore.......' And this is invaluable for the mental education of youth."--In May he was in correspondence with Professor Balfour Stewart regarding a projected movement in Terrestrial Magnetism to be submitted to the British Association. Airy cordially approved of this movement, and supported it to the best of his ability, stating that in his opinion what was mainly wanted was the collation of existing records.--In January and February he was much pressed by Prof. Pritchard of Oxford to give his opinion as to the incorrectness of statements made by Dr Kinns in his Lectures on the Scientific Accuracy of the Bible. Airy refused absolutely to take part in the controversy, but he could not escape from the correspondence which the matter involved: and this led up to other points connected with the early history of the Israelites, a subject in which he took much interest.

1885

From May 4th to June 3rd he was at Playford.--From July 2nd to 22nd he was in the Lake District. The journey was by Windermere to Kentmere, where he made enquiries concerning the Airy family, as it had been concluded with much probability from investigations made by his nephew, the Rev. Basil R. Airy, that the family was settled there at a very early date. Some persons of the name of Airy were still living there. He then went on by Coniston and Grasmere to Portinscale, and spent the rest of his time in expeditions amongst the hills and visits to friends.--On July 28th he went to Woodbridge in Suffolk and distributed the prizes to the boys of the Grammar School there.--From Oct. 9th to Nov. 12th he was again at Playford.--Throughout the year he was busily engaged on the Numerical Lunar Theory, and found but little time for miscellaneous reading.

Of printed papers by Airy in this year the most important was one on the "Results deduced from the Measures of Terrestrial Magnetic Force in the Horizontal Plane," &c. This was a long Paper, communicated to the Royal Society, and published in the Phil. Trans., and was the last Scientific Paper of any importance (except the Volume of the Numerical Lunar Theory) in the long list of "Papers by G.B. Airy." The preparation of this Paper took much time.--Of miscellaneous matters: In May a Committee of the Royal Society had been appointed to advise the India Office as to the publication of Col. J. Herschel's pendulum observations in India; and Airy was asked to assist the Committee with his advice. He gave very careful and anxious consideration to the subject, and it occupied much time.--In the early part of the year he was asked by Sir William Thomson to assist him with an affidavit in a lawsuit concerning an alleged infringement of one of his Patents for the improvement of the Compass. Airy declined to make an affidavit or to take sides in the dispute, but he wrote a letter from which the following is extracted: "I cannot have the least difficulty in expressing my opinion that you have made a great advance in the application of my method of correcting the compass in iron ships, by your introduction of the use of short needles for the compass-cards. In my original investigations, when the whole subject was in darkness, I could only use existing means for experiment, namely the long-needle compasses then existing. But when I applied mechanical theory to explanation of the results, I felt grievously the deficiency of a theory and the construction which it suggested (necessarily founded on assumption that the proportion of the needle-length to the other elements of measure is small) when the length of the needles was really so great. I should possibly have used some construction like yours, but the Government had not then a single iron vessel, and did not seem disposed to urge the enquiry. You, under happier auspices, have successfully carried it out, and, I fully believe, with much advantage to the science."--He wrote a Paper for the Athenaeum and had various correspondence on the subject of the Badbury Rings in Dorsetshire, which he (and others) considered as identical with the "Mons Badonicus" of Gildas, the site of an ancient British battle.--In February he was in correspondence with the Astronomer Royal on Uniform Time Reckoning, and on considerations relating to it.--On June 6th he attended the Annual Visitation of the Observatory, and brought before the Board his investigations of the Diurnal Magnetic Inequalities, and the revises of his Lunar Theory.

1886

From June 8th to July 17th he was at Playford.--And again at Playford from Oct. 5th to Nov. 8th.--On March 27th he had an attack of gout in his right foot, which continued through April and into May, causing him much inconvenience.--He was busy with the Numerical Lunar Theory up to Sept. 25th, when he was reading the last proof-sheet received from the printers: during this period his powers were evidently failing, and there are frequent references to errors discovered and corrected, and to uncertainties connected with points of the Theory. But his great work on the Numerical Lunar Theory was printed in this year: and there can be no doubt that he experienced a great feeling of relief when this was accomplished.--He was in correspondence with Prof. Adams as to the effect of his reduction of the Coefficient of Lunar Acceleration on the calculation of the ancient historical eclipses.--He compiled a Paper "On the establishment of the Roman dominion in England," which was printed in 1887.--He wrote a notice concerning events in the life of Mr John Jackson of Rosthwaite near Keswick, a well-known guide and much-respected authority on matters relating to the Lake District.--He also wrote a short account of the connection of the history of Mdlle de Quéroualle with that of the Royal Observatory at Greenwich.--On June 4th he attended at the Annual Visitation of the Observatory.

1887

On May 9th to 11th he made a short visit to Eastbourne and the neighbourhood.--From June 8th to July 13th he was at Playford.--From Aug. 29th to Sept. 5th he was travelling in Dorsetshire and Wiltshire: he went first to Weymouth, a very favourite centre for excursions with him, and afterwards visited Bridport and Lyme Regis: then by Dorchester to Blandford, and visited the Hod Hill, Badbury Rings, &c.: at Wimborne he was much interested in the architecture of the church: lastly he visited Salisbury, Old Sarum, Stonehenge, &c., and returned to Greenwich.--From Oct. 11th to Nov. 12th he was at Playford.--During this year he partly occupied himself with arranging his papers and drawings, and with miscellaneous reading. But he could not withdraw his thoughts from his Lunar Theory, and he still continued to struggle with the difficulties of the subject, and was constantly scheming improvements. His private accounts also now gave him much trouble. Throughout his life he had been accustomed to keep his accounts by double entry in very perfect order. But he now began to make mistakes and to grow confused, and this distressed him greatly. It never seemed to occur to him to abandon his elaborate system of accounts, and to content himself with simple entries of receipts and expenses. This would have been utterly opposed to his sense of order, which was now more than ever the ruling principle of his mind. And so he struggled with his accounts as he did with his Lunar Theory till his powers absolutely failed. In his Journal for this year there are various entries of mental attacks of short duration and other ailments ascribable to his advanced age.

The last printed "Papers by G.B. Airy" belong to this year. One was the Paper before referred to "On the establishment of the Roman dominion in England": another was on the solution of a certain Equation: and there were early reminiscences of the Cambridge Tripos, &c.--In February he attended a little to a new edition of his Ipswich Lectures, but soon handed it over to Mr H.H. Turner of the Royal Observatory.--On May 23rd he was drawing up suggestions for the arrangement of the Seckford School, &c., at Woodbridge.--On June 4th he attended the Visitation of the Royal Observatory, when a resolution was passed in favour of complete photography of the star-sky.

1888

From the 14th to 16th of May he made a short expedition to Bournemouth, and stopped on the way home to visit Winchester Cathedral.--From June 27th to Aug. 3rd he was at Playford; and again from Oct. 13th to Nov. 10th.--During the first half of the year he continued his examination of his Lunar Theory, but gradually dropped it. There are several references in his Journal to his feelings of pain and weakness, both mental and bodily: at the end of March he had an attack of gout in the fingers of his right hand. During the latter part of the year he was troubled with his private accounts, as before.--He does not appear to have been engaged on any miscellaneous matters calling for special notice in this year. But he kept up his astronomical correspondence--with Lockyer on the meteorite system of planetary formation; with Pritchard on the work of the Oxford University Observatory; with Adams on his Numerical Lunar Theory, &c., and with others.--On June 2nd he attended the Visitation of the Royal Observatory.--He amused himself occasionally with reading his favourite subjects of history and antiquities, and with looking over some of his early investigations of scientific questions.

1889

On June 5th he made a one-day's excursion to Colchester.--From July 2nd to 27th he was in the Cumberland Lake District, chiefly at Portinscale near Keswick. While staying at Portinscale he was seized with a sudden giddiness and fell upon the floor: he afterwards wrote a curious account of the visions which oppressed his brain immediately after the accident. He returned by Solihull, where his son Osmund was residing.--From Oct. 4th to Nov. 8th he was at Playford. While there he drew up a short statement of his general state of health, adverting particularly to the loss of strength in his legs and failure of his walking powers.--His health seems to have failed a good deal in this year: on Feb. 4th he had an accidental fall, and there are several entries in his Journal of mental attacks, pains in his limbs, affection of his eye-sight, &c.--In the early part of the year he was much engaged on the history of the Airy family, particularly on that of his father.--In this year the White House was sold by auction by its owners, and Airy purchased it on May 24th.--He was still in difficulties with his private accounts, but was making efforts to abandon his old and elaborate system.--For his amusement he was chiefly engaged on Theological Notes which he was compiling: and also on early optical investigations, &c.

On June 1st he attended the Visitation of the Royal Observatory, and moved a resolution that a Committee be appointed to consider whether any reduction can be effected in the amount of matter printed in the Volume of Observations of the Royal Observatory. During his tenure of office he had on various occasions brought this subject before the Board of Visitors, and with his usual tenacity of purpose he now as Visitor pressed it upon their notice.--In May he zealously joined with others in an application to get for Dr Huggins a pension on the Civil List.--In January he prepared a short Paper illustrated with diagrams to exhibit the Interference of Solar Light, as used by him in his Lectures at Cambridge in 1836: but it does not appear to have been published.--In April he received a copy of a Paper by Mr Rundell, referring to the complete adoption of his system of compass correction in iron ships, not only in the merchant service, but also in the Navy. This was a matter of peculiar gratification to Airy, who had always maintained that the method of Tables of Errors, which had been so persistently adhered to by the Admiralty, was a mistake, and that sooner or later they would find it necessary to adopt his method of mechanical correction. The passage referred to is as follows: "The name of Sir George Airy, the father of the mechanical compensation of the compass in iron vessels, having just been mentioned, it may not be inappropriate to remind you that the present year is the fiftieth since Sir George Airy presented to the Royal Society his celebrated paper on this subject with the account of his experiments on the 'Rainbow' and 'Ironsides.' Fifty years is a long period in one man's history, and Sir George Airy may well be proud in looking back over this period to see how complete has been the success of his compass investigation. His mode of compensation has been adopted by all the civilized world. Sir William Thomson, one of the latest and perhaps the most successful of modern compass adjusters, when he exhibited his apparatus in 1878 before a distinguished meeting in London, remarked that within the last ten years the application of Sir George Airy's method had become universal, not only in the merchant service, but in the navies of this and other countries, and added--The compass and the binnacles before you are designed to thoroughly carry out in practical navigation the Astronomer Royal's principles."

1890

From May 17th to 24th he was on an expedition to North Wales, stopping at Chester, Conway, Carnarvon, Barmouth, and Shrewsbury.--From June 18th to July 24th he was at Playford; and again from Oct. 11th to Nov. 15th.--In this year his powers greatly failed, and he complained frequently of mental attacks, weakness of limbs, lassitude, and failure of sleep. He occupied himself as usual with his books, papers, and accounts; and read Travels, Biblical History, &c., but nothing very persistently.

On June 7th he attended the Visitation of the Royal Observatory.--From a letter addressed to him by Mr J. Hartnup, of Liverpool Observatory, it appears that there had grown up in the mercantile world an impression that very accurate chronometers were not needed for steam ships, because they were rarely running many days out of sight of land: and Airy's opinion was requested on this matter. He replied as follows on Mar. 3rd: "The question proposed in your letter is purely a practical one. (1) If a ship is likely ever to be two days out of sight of land, I think that she ought to be furnished with two good chronometers, properly tested. (2) For the proper testing of the rates of the chronometers, a rating of the chronometers for three or four days in a meridional observatory is necessary. A longer testing is desirable."--In March he was in correspondence, as one of the Trustees of the Sheepshanks Fund, with the Master of Trinity relative to grants from the Fund for Cambridge Observatory.

1891

From June 16th to July 15th he was at Playford. And again from Oct. 12th to Dec. 2nd (his last visit). Throughout the year his weakness, both of brain power and muscular power, had been gradually increasing, and during this stay at Playford, on Nov. 11th, he fell down in his bed-room (probably from failure of nerve action) and was much prostrated by the shock. For several days he remained in a semi-unconscious condition, and although he rallied, yet he continued very weak, and it was not until Dec. 2nd that he could be removed to the White House. Up to the time of his fall he had been able to take frequent drives and even short walks in the neighbourhood that he was so fond of, but he could take but little exercise afterwards, and on or about Nov. 18th he made the following note: "The saddest expedition that I have ever made. We have not left home for several days."

The rapid failure of his powers during this year is well exemplified by his handwriting in his Journal entries, which, with occasional rallies, becomes broken and in places almost illegible. He makes frequent reference to his decline in strength and brain-power, and to his failing memory, but he continued his ordinary occupations, made frequent drives around Blackheath, and amused himself with his family history researches, arrangement of papers, and miscellaneous reading: and he persisted to the last with his private accounts. His interest in matters around him was still keen. On June 13th he was driving along the Greenwich Marshes in order to track the course of the great sewer; and on August 5th he visited the Crossness Sewage Works and took great interest in the details of the treatment of the sewage.--In March he contributed, with great satisfaction, to the Fund for the Portrait of his old friend Sir G.G. Stokes, with whom he had had so much scientific correspondence.--On July 25th an afternoon party was arranged to celebrate the 90th anniversary of his birthday (the actual anniversary was on July 27th). None of his early friends were there: he had survived them all. But invitations were sent to all his scientific and private friends who could be expected to come, and a large party assembled. The afternoon was very fine, and he sat in the garden and received his friends (many of whom had come from long distances) in good strength and spirits. It was a most successful gathering and was not without its meaning; for it was felt that, under the circumstances of his failing powers, it was in all probability a final leave-taking.--On July 27th he went down to the Greenwich Parish Church at 9 p.m., to be present at the illumination of the church clock face for the first time--a matter of local interest which had necessitated a good deal of time and money. On this occasion at the request of the company assembled in and around the Vestry he spoke for about a quarter of an hour on Time--the value of accurate time, the dissemination of Greenwich time throughout the country by time-signals from the Observatory, and the exhibition of it by time-balls, &c., &c.,--the subject to which so large a part of his life had been devoted. It was a pleasant and able speech and gave great satisfaction to the parishioners, amongst whom he had lived for so many years.--He received two illuminated addresses--one from the Astronomer Royal and Staff of the Royal Observatory; the other from the Vorstand of the Astronomische Gesellschaft at Berlin--and various private letters of congratulation. The address from the Staff of the Observatory was worded thus: "We, the present members of the Staff of the Royal Observatory, Greenwich, beg to offer you our most sincere congratulations on the occasion of your 90th birthday. We cannot but feel how closely associated we are with you, in that our whole energies are directed to the maintenance and development of that practical astronomical work, of which you essentially laid the foundation. It affords us great pleasure to think that after the conclusion of your life's work, you have been spared to live so long under the shadow of the noble Observatory with which your name was identified for half a century, and with which it must ever remain associated."

After his return from Playford he seemed to rally a little: but he soon fell ill and was found to be suffering from hernia. This necessitated a surgical operation, which was successfully performed on Dec. 17th. This gave him effectual relief, and after recovering from the immediate effects of the operation, he lay for several days quietly and without active pain reciting the English poetry with which his memory was stored. But the shock was too great for his enfeebled condition, and he died peacefully in the presence of his six surviving children on Jan. 2nd, 1892. He was buried in Playford churchyard on Jan. 7th. The funeral procession was attended at Greenwich by the whole staff of the Royal Observatory, and by other friends, and at his burial there were present two former Fellows of the College to which he had been so deeply attached.

APPENDIX.

LIST OF PRINTED PAPERS BY G.B. AIRY.

LIST OF BOOKS WRITTEN BY G.B. AIRY.

PRINTED PAPERS BY G.B. AIRY.

With the instinct of order which formed one of his chief characteristics Airy carefully preserved a copy of every printed Paper of his own composition. These were regularly bound in large quarto volumes, and they are in themselves a striking proof of his wonderful diligence. The bound volumes are 14 in number, and they occupy a space of 2 ft. 6 in. on a shelf. They contain 518 Papers, a list of which is appended, and they form such an important part of his life's work, that his biography would be very incomplete without a reference to them.

He was very careful in selecting the channels for the publication of his Papers. Most of the early Papers were published in the Transactions of the Cambridge Philosophical Society, but several of the most important, such as his Paper "On an inequality of long period in the motions of the Earth and Venus," were published in the Philosophical Transactions of the Royal Society, and others, such as the articles on "The Figure of the Earth," "Gravitation," "Tides and Waves," &c., were published in Encyclopaedias. After his removal to Greenwich nearly all his Papers on scientific subjects (except astronomy), such as Tides, Magnetism, Correction of the Compass, &c., &c., were communicated to the Royal Society, and were published in the Philosophical Transactions. But everything astronomical was reserved for the Royal Astronomical Society. His connection with that Society was very close: he had joined it in its earliest days (the date of his election was May 9th, 1828), and regarded it as the proper medium for the discussion of current astronomical questions, and for recording astronomical progress. He was unremitting in his attendance at the Monthly Meetings of the Society, and was several times President. In the Memoirs of the Society 35 of his Papers are printed, and in addition 129 Papers in the Monthly Notices. In fact a meeting of the Society rarely passed without some communication from him, and such was his wealth of matter that sometimes he would communicate as many as 3 Papers on a single evening. For the publication of several short mathematical Papers, and especially for correspondence on disputed points of mathematical investigation, he chose as his vehicle the Philosophical Magazine, to which he contributed 32 Papers. Investigations of a more popular character he published in the Athenaeum, which he also used as a vehicle for his replies to attacks on his work, or on the Establishment which he conducted: in all he made 55 communications to that Newspaper. To various Societies, such as the Institution of Civil Engineers, the British Association, the Royal Institution, &c., he presented Papers or made communications on subjects specially suited to each; and in like manner to various Newspapers: there were 58 Papers in this category. In so long an official life there would naturally be a great number of Official Reports, Parliamentary Returns, &c., and these, with other miscellaneous Papers printed for particular objects and for a limited circulation, amounted in all to 141. Under this head come his Annual Reports to the Board of Visitors, which in themselves contain an extremely full and accurate history of the Observatory during his tenure of office. There are 46 of these Reports, and they would of themselves form a large volume of about 740 pages.

The following summary of his Printed Papers shews the manner in which they were distributed:

SUMMARY OF PRINTED PAPERS BY G.B. AIRY.

Number of Papers.

In the Transactions of the Cambridge Philosophical Society 30 In the Philosophical Transactions of the Royal Society 29 In the Proceedings of the Royal Society 9 In the Memoirs of the Royal Astronomical Society 35 In the Monthly Notices of the Royal Astronomical Society 129 In the Philosophical Magazine and Journal 32 In the Athenaeum 55 In Encyclopedias, and in various Newspapers and Transactions 58 In Official Reports, Addresses, Parliamentary Returns, Evidence before Committees, Lectures, Letters, Sundry Treatises, and Papers 141 --- Total 518

PRINTED PAPERS BY G.B. AIRY.

Date when read or published. Title of Paper. Where published.

1822 Nov. 25 On the use of Silvered Glass for the Mirrors Camb. Phil. Soc. of Reflecting Telescopes.

1824 Mar. 15 On the Figure assumed by a Fluid Homogeneous Camb. Phil. Soc. Mass, whose Particles are acted on by their mutual Attraction, and by small extraneous Forces.

1824 May 17 On the Principles and Construction of the Camb. Phil. Soc. Achromatic Eye-Pieces of Telescopes, and on the Achromatism of Microscopes.

1824 Trigonometry. Encycl. Metrop.

1825 Feb. 21 On a peculiar Defect in the Eye, and a Camb. Phil. Soc. mode of correcting it.

1825 May 2 On the Forms of the Teeth of Wheels. Camb. Phil. Soc.

1826 May 8 On Laplace's Investigation of the Attraction Camb. Phil. Soc. of Spheroids differing little from a Sphere.

1826 June 15 On the Figure of the Earth. Phil. Trans.

1826 Nov. 26 On the Disturbances of Pendulums and Camb. Phil. Soc. Balances, and on the Theory of Escapements.

1827 Feb. 15 Remarks on a Correction of the Solar Phil. Trans. Tables, required by Mr South's observations.

1827 May 9 On some Passages in Mr Ivory's Remarks Phil. Mag. on a Memoir by M. Poisson relating to the Attraction of Spheroids.

1827 May 14 On the Spherical Aberration of the Camb. Phil. Soc. May 21 Eyepieces of Telescopes.

1827 Dec. 6 On the corrections in the elements of Phil. Trans. Delambre's Solar Tables required by the observations made at the Royal Observatory, Greenwich.

1828 Feb. 26 Address to the Members of the Senate, on an Improvement in the Position of the Plumian Professor.

1828 Nov. 24 On the Longitude of the Cambridge Observatory. Camb. Phil. Soc.

1829 Nov. 13 On a method of determining the Mass of Astr. Soc. the Moon from Transit Observations of (Memoirs) Venus near her inferior conjunction.

1829 Nov. 16 On a Correction requisite to be applied Camb. Phil. Soc. to the Length of a Pendulum consisting of a Ball suspended by a fine Wire.

1829 Dec. 14 On certain Conditions under which a Camb. Phil. Soc. Perpetual Motion is possible.

1830 Aug. 17 Figure of the Earth. Encycl. Metrop.

1831 Feb. 21 On the Nature of the Light in the Two Camb. Phil. Soc. Rays produced by the Double Refraction of Quartz.

1831 Apr. 18 Addition to the above Paper. Camb. Phil. Soc.

1831 Nov. 14 On a remarkable Modification of Newton's Camb. Phil. Soc. Rings.

1831 Nov. 24 On an inequality of long period in the Phil. Trans. motions of the Earth and Venus.

1832 Jan. 2 Translation of Encke's Dissertation (on Encke's Comet) contained in Nos. 210 and 211 of the Astronomische Nachrichten.

1833 Mar. 5 On a new Analyzer, and its use in Camb. Phil. Soc. Experiments of Polarization.

1832 Mar. 19 On the Phenomena of Newton's Rings when formed between two transparent Substances of different refractive Powers.

1832 May 2 Report on the Progress of Astronomy Trans Brit. Ass. during the present century.

1832 Oct. Report of the Syndicate of the Cambridge Observatory.

1833 Feb. 2 Remarks on Mr Potter's Experiment on Phil. Mag. Interference.

1833 Apr. 12 On the Mass of Jupiter, as determined R. Astr. Soc. from the Observation of Elongations of (Memoirs) the Fourth Satellite.

1833 Syllabus of a Course of Experimental Lectures.

1833 May 7 On the Calculation of Newton's Camb. Phil. Soc. Experiments on Diffraction.

1833 May 7 Remarks on Sir David Brewster's Paper Phil. Mag. "On the Absorption of Specific Rays" &c.

1833 May 16 Results of the Repetition of Mr Potter's Phil. Mag. Experiment of interposing a Prism in the Path of Interfering Light.

1833 May On a supposed black bar formed by Phil. Mag. Diffraction.

1833 June 20 Report on Mr Barlow's Fluid-Lens R. Soc. (Proc.) Telescope

1834 Mar. 14 Continuation of Researches into the Value R. Astr. Soc. of the Mass of Jupiter, by observation of (Memoirs.) the Elongations of the Fourth Satellite.

1834 Apr. 14 On the Latitude of Cambridge Observatory Camb. Phil. Soc.

1834 June Report of the Syndicate of the Cambridge Observatory.

1834 June 13 On the Position of the Ecliptic, as inferred R. Astr. Soc. inferred from Transit and Circle (Memoirs.) Observations made at Cambridge Observatory in the year 1833.

1834 June 13 Observations of the Solar Eclipse of July R. Astr. Soc. 16th, 1833, made at Cambridge Observatory, (Memoirs.) and Calculations of the Observations.

1834 Nov. 24 On the Diffraction of an Object-Glass Camb. Phil. Soc. with Circular Aperture.

1834 Dec. 3 On the Calculation of the Perturbations Naut. Alm. of the Small Planets and the Comets of (1837, App.) short period.

1835 May 8 Continuation of Researches into the Value R. Astr, Soc. of Jupiter's Mass. (Memoirs.)

1835 June Report of the Syndicate of the Cambridge Observatory.

1835 June 12 On the Position of the Ecliptic, as R. Astr. Soc. inferred from Observations with the (Memoirs.) Cambridge Transit and Mural Circle, made in the year 1834.

1835 June 12 On the Time of Rotation of Jupiter. R. Astr. Soc. (Memoirs.)

1836 Feb. 12 Speech on delivering the Medal of the R. Astr. Soc. R. Astr. Soc. to Sir John Herschel. (Proc.)

1836 June 4 Report of the Astronomer Royal to the Board of Visitors.

1836 June 9 Report upon a Letter (on a Systematic R. Soc. Course of Magnetic Observations) addressed (Proc.) by M. le Baron de Humboldt to His Royal Highness the President of the Royal Society (by S. Hunter Christie and G.B. Airy).

1837 Jan. 13 Continuation of Researches into the Value R. Astr. Soc. of Jupiter's Mass. (Memoirs.)

1837 Feb. 10 Speech on delivering the Medal of the R. Astr. Soc. R. Astr. Soc. to Professor Rosenberger. (Proc)

1837 Mar. 10 Results of the Observations of the Sun, R. Astr. Soc. Moon, and Planets, made at Cambridge (Memoirs) Observatory in the years 1833, 1834, and 1835.

1837 May 12 On the Position of the Ecliptic, as R. Astr. Soc. inferred from Observations with the (Memoirs) Cambridge Transit and Mural Circle, made in the year 1835.

1837 June 3 Report of the Astronomer Royal to the Board of Visitors.

1837 Sept. 9 Address delivered in the Town Hall of Neath.

1837 Nov. 10 On the Parallax of alpha Lyrae. R. Astr. Soc. (Memoirs.)

1838 Feb. 10 Address to the Earl of Burlington on Religious Examination in the University of London.

1838 Mar. 26 On the Intensity of Light in the Camb. Phil. Soc. neighbourhood of a Caustic.

1838 June 2 Report of the Astronomer Royal to the Board of Visitors.

1838 Dec. 14 A Catalogue of 726 Stars, deduced from R. Astr. Soc. the Observations made at the Cambridge (Memoirs.) Observatory, from 1828 to 1835; reduced to January 1, 1830.

1839 Apr. 25 Account of Experiments on Iron-built Phil. Trans. Ships, instituted for the purpose of discovering a correction for the deviation of the Compass produced by the iron of the Ships.

1839 June 1 Report of the Astronomer Royal to the Board of Visitors.

1839 Nov. 8 On the Determination of the Orbits of R. Astr. Soc. Comets, from Observations. (Memoirs.)

1839 Article "Gravitation." Penny Cyclop.

1839 Article "Greenwich Observatory." Penny Cyclop.

1840 Mar. 2 On a New Construction of the Camb. Phil. Soc. Going-Fusee.

1840 Mar. 13 On the Regulator of the Clock-work for R. Astr. Soc. effecting uniform Movement of Equatoreals.

1840 May 15 On the Correction of the Compass in Un. Serv. Journ. Iron-built Ships. (Proc.)

1840 Results of Experiments on the Disturbance J. Weale. of the Compass in Iron-built Ships.

1840 June 6 Report of the Astronomer Royal to the Board of Visitors.

1840 June 18 On the Theoretical Explanation of an Phil. Trans. apparent new Polarity in Light.

1840 Nov. 19 Supplement to the above Paper. Phil. Trans.

1840 Dec. 4 On the Diffraction of an Annular Aperture. Phil. Mag.

1840 Dec. 9 Remarks on Professor Challis's Investigation Phil. Mag. of the Motion of a Small Sphere vibrating in a Resisting Medium.

1841 Jan. 20 Correction to the above Paper "On the Phil. Mag. Diffraction," &c.

1841 Mar. 22 Remarks on Professor Challis's Reply to Phil. Mag. Mr Airy's Objections to the Investigation of the Resistance of the Atmosphere to an Oscillating Sphere.

1841 June 5 Report of the Astronomer Royal to the Board of Visitors.

1841 July 10 Reply to Professor Challis, on the Phil. Mag. Investigation of the Resistance of the Air to an Oscillating Sphere.

1841 Oct. 26 Extraordinary Disturbance of the Magnets.

1841 Nov. 25 On the Laws of the Rise and Fall of the Phil. Trans. Tide in the River Thames.

1841 Dec. 21 Report of the Commissioners appointed to consider the steps to be taken for Restoration of the Standards of Weight and Measure.

1842 Apr. 16 On the [Greek: Ichtis] of Diodorus Athenaeum.

1842 May 13 Account of the Ordnance Zenith Sector. R. Astr. Soc. (Proc.)

1842 June 4 Report of the Astronomer Royal to the Board of Visitors.

1842 Nov. 11 Observations of the Total Solar Eclipse of R. Astr. Soc. 1842 July 7. (Memoirs.)

1842 Dec. 1 Remarks on the Present State of Hatcliff's Private Charity (Greenwich).

1842 Article on Tides and Waves. Encyc. Metrop.

1843 Mar. 2 On the Laws of Individual Tides at Phil. Trans. Southampton and at Ipswich.

1843 Apr. 29 On Monetary and Metrical Systems. Athenaeum.

1843 June 3 Report of the Astronomer Royal to the Board of Visitors.

1843 Sept. 25 Address to the Individual Members of the Board of Visitors of the Royal Observatory (proposing the Altazimuth).

1843 Oct. 6 Account of the Northumberland Equatoreal and Dome, attached to the Cambridge Observatory.

1843 Nov. 10 Address and Explanation of the proposed Altitude and Azimuth Instrument to the Board of Visitors of the Royal Observatory.

1844 June 1 Report of the Astronomer Royal to the Board of Visitors.

1844 Dec. 12 On the Laws of the Tides on the Coasts of Phil. Trans. Ireland, as inferred from an extensive series of observations made in connection with the Ordnance Survey of Ireland.

1845 Jan. 10 On the Flexure of a Uniform Bar R. Astr. Soc. supported by a number of equal Pressures (Memoirs.) applied at equidistant points, &c.

1845 Feb. 14 Speech on delivering the Medal of the R. Astr. Soc. R. Astr. Soc. to Capt. Smyth (Proc.)

1845 May 9 On a New Construction of the Divided R. Astr. Soc. Eye-Glass Double-Image Micrometer. (Memoirs.)

1845 June 7 Report of the Astronomer Royal to the Board of Visitors.

1845 July 21 On Wexford Harbour.

1846 Report of the Gauge Commissioners. And letter to Sir E. Ryan.

1846 May 7 On the Equations applying to Light under Phil. Mag. the action of Magnetism.

1846 May 12 Remarks on Dr Faraday's Paper on Phil. Mag. Ray-vibrations.

1846 May 25 On a Change in the State of an Eye Camb. Phil. Soc. affected with a Mal-formation.

1846 June 6 Report of the Astronomer Royal to the Board of Visitors.

1846 June Account of the Measurement of an Arc of R. Astr. Soc. Longitude between the Royal Observatory (Month. Not.) of Greenwich and the Trigonometrical Station of Feagh Main, in the Island of Valentia.

1846 July 25 Letter to Sir Robert Harry Inglis, Bart., Athenaeum. M.P., in answer to Sir James South's attack on the Observations at the Greenwich Observatory.

1846 Nov. On the Bands formed by the partial Phil. Mag. Interception of the Prismatic Spectrum.

1846 Nov. 13 Account of some circumstances historically R. Astr. Soc. connected with the Discovery of the (Memoirs.) Planet exterior to Uranus.

1847 Jan. 8 Reduction of the Observations of Halley's R. Astr. Soc. Comet made at the Cambridge Observatory in (Memoirs.) the years 1835 and 1836.

1847 Jan. 8 On a proposed Alteration of Bessel's Method R. Astr. Soc. for the Computation of the Corrections by (Memoirs.) which the Apparent Places of Stars are derived from the Mean Places.

1847 Feb. On Sir David Brewster's New Analysis of Phil. Mag. Solar Light.

1847 Feb. 20 On the Name of the New Planet. Athenaeum.

1847 Feb. 27 Mr Adams and the New Planet. Athenaeum.

1847 Plan of the Buildings and Grounds of the Royal Observatory, Greenwich, with Explanation and History.

1847 May 14 Explanation of Hansen's Perturbations of R. Astr. Soc. the Moon by Venus. (Month. Not.)

1847 June 5 Report of the Astronomer Royal to the Board of Visitors.

1847 Nov. 30 Address to the Individual Members of the Board of Visitors of the Royal Observatory. (Zenith Tube.)

1847 Dec. 10 Results deduced from the Occultations of R. Astr. Soc. Stars and Planets by the Moon, observed (Memoirs.) at Cambridge Observatory from 1830 to 1835.

1848 Feb. 11 Abstract of Struve's "Études d'Astronomie R. Astr. Soc. Stellaire." (Month. Not.)

1848 Mar. 13 Syllabus of Lectures on Astronomy to be delivered at the Temperance Hall, Ipswich.

1848 Apr. 10 Remarks on Prof. Challis's Theoretical Phil. Mag. Determination of the Velocity of Sound

1848 May 8 Supplement to a Paper on the Intensity of Camb. Phil. Soc. Light in the neighbourhood of a Caustic.

1848 May 12 Address to Individual members of the Board of Visitors. (New Transit Circle, Reflex Zenith Tube, &c.)

1848 June 3 Report of the Astronomer Royal to the Board of Visitors.

1848 June 9 Corrections of the Elements of the Moon's R. Astr. Soc. Orbit, deduced from the Lunar (Memoirs.) Observations made at the Royal Observatory, of Greenwich from 1750 to 1830.

1848 Aug. 9 Explanation of a proposed construction of Zenith Sector: addressed to the Board of Visitors of the Royal Observatory, Greenwich.

1848 Oct. 14 On the Construction of Chinese Balls Athenaeum.

1849 Description of the Instruments of Process used in the Photographic self-registration of the Magnetical and Meteorological Instruments at the Royal Observatory, Greenwich.

1849 Description of the Altitude and Azimuth Instrument erected at the Royal Observatory, Greenwich, in the year 1847.

1849 Astronomy. (Tract written for the Scientific Manual.)

1849 Mar. 9 Substance of the Lecture delivered by the R. Astr. Soc. Astronomer Royal on the large Reflecting (Month. Not.) Telescopes of the Earl of Rosse and Mr Lassell.

1849 June On a difficulty in the problem of Sound. Phil. Mag.

1849 June 2 Report of the Astronomer Royal to the Board of Visitors.

1849 June 8 On Instruments adapted to the Measure of R. Astr. Soc. small Meridional Zenith Distances. (Month. Not.)

1849 Nov. 9 Results of the Observations made by the R. Astr. Soc. Rev. Fearon Fallows at the Royal (Memoirs.) Observatory, Cape of Good Hope, in the years 1829, 1830, 1831.

1849 Nov. 9 On Bell's Calculating machine, and on R. Astr. Soc. Lord Rosse's Telescope. (Month. Not.)

1849 Nov. 10 On the Exodus of the Israelites. Athenaeum.

1849 Dec. 14 On the Method of observing and recording R. Astr. Soc. Transits, lately introduced in America, &c. (Month. Not.)

1850 Jan. 10 On a problem of Geodesy. Phil. Mag.

1850 Feb. 8 Address on presenting the Medal of the R. Astr. Soc. R. Astr. Soc. to M. Otto von Struve. (Month. Not.)

1850 Mar. 15 On the Present State and Prospects of the R. Inst. Science of Terrestrial Magnetism.

1850 Mar. 16 On the Exodus of the Israelites Athenaeum.

1850 Mar. 30 On the Exodus of the Israelites. Athenaeum.

1850 May 10 Statement concerning Assistance granted R. Astr. Soc. by the Admiralty to Hansen--Also on (Month. Not.) Henderson's numbers for the teeth of wheels.

1850 May 10 On the Weights to be given to the separate R. Astr. Soc. Results for Terrestrial Longitudes, (Memoirs.) determined by the observation of Transits of the Moon and Fixed Stars.

1850 June 1 Report of the Astronomer Royal to the Board of Visitors.

1850 June 14 Letter from Hansen on his Lunar Tables.--Valz R. Astr. Soc. on an arrangement of double-image (Month. Not.) micrometer.--On the Computation of Longitude from Lunar Transits

1850 Dec. 13 On a Method of regulating the Clock-work R. Astr. Soc. for Equatoreals. (Month. Not.)

1850 Dec. 13 Supplement to a Paper "On the Regulation R. Astr. Soc. of the Clock-work for effecting Uniform (Memoirs.) Movement of Equatoreals."

1850 Dec. 27 On the Relation of the Direction of the Phil. Trans. Wind to the Age of the Moon, as inferred from Observations made at the Royal Observatory, Greenwich, from 1840 Nov. to 1847 Dec.

1851 Jan. 14 Remarks on Mr Wyatt's Paper on the Inst. C.E. Construction of the Building for the (Minutes.) Exhibition of the Works of Industry of all Nations in 1851.

1851 Feb. 15 Address on presenting the medal of the R. Astr. Soc. R. Astr. Soc. to Dr Annibale de (Month. Not.) Gasparis.

1851 Mar. 28 Letter to Professor Challis regarding the Adams Prize.

1851 Mar. 29 On Caesar's place of landing in Britain. Athenaeum.

1851 Suggestions to Astronomers for the Brit. Assoc. Observation of the Total Eclipse of the Sun on July 28, 1851.

1851 Apr. 11 On the Determination of the probable R. Astr. Soc. Stability of an Azimuthal Circle by (Month. Not.) Observations of Star and a permanent Collimator.

1851 May 2 On the Total Solar Eclipse of 1851, July 28. R. Inst. (Lecture.)

1851 May 9 On the Vibration of a Free Pendulum in an R. Astr. Soc. Oval differing little from a Straight Line (Memoirs)

1851 June 7 Report of the Astronomer Royal to the Board of Visitors.

1851 July 2 The President's Address to the Twenty-first Athenaeum. Meeting of the British Association for the Advancement of Science, Ipswich.

1851 Oct. 17 On Julius Caesar's Expedition against Naut. Mag. England, in relation to his places of departure and landing.

1851 Nov. 14 Account of the Total Eclipse of the Sun on R. Astr. Soc. 1851, July 28, as observed at Göttenburg, (Memoirs.) at Christiania, and at Christianstadt.

1851 Dec. 13 On the Geography of the Exodus. Athenaeum.

1852 Jan. 9 On the Solar Eclipse of July 28, 1851. R. Astr. Soc. (Month. Not.)

1852 On the place of Caesar's Departure from Soc. of Antiq. Gaul for the Invasion of Britain, and (Memoirs.) the Place of his Landing in Britain, with an Appendix on the Battle of Hastings.

1852 On a New Method of computing the Naut. Alm. 1856, Perturbations of planets, by J.F. App. Encke--translated and illustrated with notes by G.B. Airy.

1852 June 5 Report of the Astronomer Royal to the Board of Visitors.

1853 Feb. 3 On the Eclipses of Agathocles, Thales, Phil. Trans. and Xerxes.

1853 Feb. 4 Lecture on the results of recent R. Inst. calculations on the Eclipse of Thales and Eclipses connected with it.

1853 May 3 Address to the Individual Members of the Board of Visitors of the Royal Observatory, Greenwich. (Lunar Reductions.)

1853 May 14 On Decimal Coinage. Athenaeum.

1853 June 4 Report of the Astronomer Royal to the Board of Visitors.

1853 June Lecture on the Determination of the R. Astr. Soc. Longitude of the Observatory of (Month. Not.) Cambridge by means of Galvanic Signals.

1853 Sept. 10 On Decimal Coinage. Athenaeum.

1853 Dec. 14 Description of the Transit Circle of the Royal Observatory, Greenwich. (App. Gr. Observ. 1852.)

1853 Dec. 14 Regulations of the Royal Observatory, Greenwich. (App. Gr. Observ. 1852.)

1854 Jan. 14 On the Telegraphic Longitude of Brussels. Athenaeum.

1854 Feb. 10 Address on presenting the Gold Medal of R. Astr. Soc. the R. Astr. Soc. to Mr Charles Rümker. (Month. Not.)

1854 Feb. 25 On Reforms in the University of Cambridge. Athenaeum.

1854 Apr. 15 Letters relating to "The Late M. Mauvais." Liter. Gaz.

1854 June 3 Report of the Astronomer Royal to the Board of Visitors.

1854 Sept. The Deluge. Private.

1854 Oct. 28 On the Correction of the Compass in Iron Athenaeum. Ships. (Scoresby's Experiments.)

1854 Nov. 10 On the Difference of Longitude between R. Astr. Soc. the Observatories of Brussels and Greenwich, (Memoirs.) as determined by Galvanic Signals.

1855 Jan. 1 Lecture at S. Shields on the Pendulum Experiments in the Harton Pit, and Letter on the Results.

1855 Feb. 2 Lecture on the Pendulum Experiments R. Inst. lately made in the Harton Colliery for ascertaining the mean Density of the Earth.

1855 Feb. 3 On the Correction of the Compass in Iron Athenaeum. Ships. (Remarks on Dr Scoresby's Investigations.)

1855 Address on presenting the Medal of the R. Astr. Soc. R. Astr. Soc. to the Rev. William Rutter (Month. Not.) Dawes.

1855 Feb. 15 On the Computation of the Effect of the Phil. Trans. Attraction of Mountain Masses, as disturbing the Apparent Astronomical Latitude of Stations in Geodetic Surveys.

1855 June 2 Report of the Astronomer Royal to the Board of Visitors.

1855 Oct. 18 Address to the Individual Members of the Board of Visitors of the Royal Observatory, Greenwich. (Equatoreal.)

1855 Nov. 21 Remarks upon certain Cases of Personal R. Astr. Soc. Equation which appear to have hitherto (Memoirs.) escaped notice, accompanied with a Table of Results.

1855 Nov. 22 Discussion of the Observed Deviations of Phil. Trans. the Compass in several Ships, Wood-built and Iron-built: with a General Table for facilitating the examination of Compass-Deviations.

1855 Description of the Reflex Zenith Tube of the Royal Observatory, Greenwich. (App. to the Greenwich Obs. for 1854.)

1856 Jan. 9 On Professor Peirce's Criterion for Astr. Journ. discordant observations. (Cambr.)

1856 Jan. 24 Account of Pendulum Experiments undertaken Phil. Trans. in the Harton Colliery, for the purpose of determining the Mean Density of the Earth.

1856 June 7 Report of the Astronomer Royal to the Board of Visitors.

1856 Aug. 25 On Scheutz's Calculating Machine. Phil. Mag.

1856 Aug. 30 Science and the Government. (Reply to Athenaeum. statements in the Morning Chronicle about the instrumental equipment of the Royal Observatory.)

1857 May 8 On the Means which will be available for R. Astr. Soc. correcting the Measure of the Sun's (Month. Not.) Distance in the next twenty-five years.

1857 May 12 Knowledge expected in Computers and Assistants in the Royal Observatory.

1857 June 6 Report of the Astronomer Royal to the Board of Visitors.

1857 June 12 On the Eclipse of Agathocles, the Eclipse R. Astr. Soc. at Larissa, and the Eclipse of Thales. (Memoirs.) With an Appendix on the Eclipse of Stiklastad.

1857 June 18 Account of the Construction of the New Phil. Trans. National Standard of Length, and of its principal copies.

1857 Dec. 5 Letter to the Vice-Chancellor of Cambridge University regarding Smith's Prizes.

1857 Dec. 7 On the Substitution of Methods founded Camb. Phil. Soc. on Ordinary Geometry for Methods based on the General Doctrine of Proportions, in the treatment of some Geometrical Problems

1857 Description of the Galvanic Chronographic Gr. Obs. 1856, Apparatus of the Royal Observatory, App. Greenwich.

1858 Mar. 8 Suggestions for Observation of the Annular Eclipse of the Sun on 1858, March 14-15.

1858 Mar. 12 Note on Oltmann's Calculation of the R. Astr. Soc. Eclipse of Thales. Also On a Method (Month. Not.) of very approximately representing the Projection of a Great Circle upon Mercator's Chart.

1858 May The Atlantic Cable Problem. Naut. Mag.

1858 May 20 Report of the Ordnance Survey Commission; together with Minutes of Evidence and Appendix.

1858 June 5 Report of the Astronomer Royal to the Board of Visitors.

1858 June 16 On the Mechanical Conditions of the Phil. Mag. Deposit of a Submarine Cable.

1858 July Instructions and Chart for Observations R. Astr. Soc. of Mars in right ascension at the (Special.) Opposition of 1860 for obtaining the Measure of the Sun's Distance.

1858 Aug. 20 On the Advantageous Employment of Photog. Notes. Stereoscopic Photographs for the representation of Scenery.

1858 Nov. 6 On the "Draft of Proposed New Statutes Athenaeum. for Trinity College, Cambridge."

1858 Nov. 20 Letter to the Vice-Chancellor of the University of Cambridge, offering the Sheepshanks Endowment.

1858 Dec. 6 Suggestion of a Proof of the Theorem Camb. Phil. Soc. that Every Algebraic Equation has a Root.

1859 Manual of Astronomy--for the Admiralty. Parly. Paper.

1859 Feb. 1 Letter to Lord Monteagle relating to the Standards of Weights and Measures.

1859 Feb. 4 Remarks on Mr Cayley's Trigonometrical Phil. Mag. Theorem, and on Prof. Challis's Proof that Equations have Roots.

1859 Mar. 11 On the Movement of the Solar System in R. Astr. Soc. Space. (Memoirs.)

1859 Apr. 8 On the Apparent Projection of Stars upon R. Astr. Soc. the Moon's Disc in Occultations. Also (Month. Not.) Comparison of the Lunar Tables of Burckhardt and Hansen with Observations of the Moon made at the Royal Observatory, Greenwich.

1859 Apr. 8 On the Apparent Projection of Stars upon R. Astr. Soc. the Moon's Disc in Occultations. (Memoirs.)

1859 June 4 Report of the Astronomer Royal to the Board of Visitors.

1859 June 10 Abstract of Maxwell's Paper "On the R. Astr. Soc. Stability of the Motion of Saturn's Rings." (Month. Not.)

1859 July 8 Corrections of the Elements of the Moon's R. Astr. Soc. Orbit, deduced from the Lunar Observations (Memoirs.) made at the Royal Observatory of Greenwich from 1750 to 1851.

1859 Sept. 10 On the Invasion of Britain by Julius Caesar. Athenaeum. (Answer to Mr Lewin.)

1859 Nov. 12 On Iron Ships--The Royal Charter. Athenaeum. (Answer to Archibald Smith's Remarks.)

1859 Nov. Circular requesting observations of small Planets.

1859 Dec. 9 Notice of the approaching Total Eclipse of R. Astr. Soc. the Sun of July 18,1860, and suggestions (Month. Not.) for observation.

1859 Dec. 12 Supplement to A Proof of the Theorem Camb. Phil. Soc. that Every Algebraic Equation has a Root.

1860 Jan. 13 Description of the New Equatoreal at the R. Astr. Soc. Royal Observatory, Greenwich. Also (Month. Not.) Abstract of an Essay by Gen. T.F. de Schubert on the Figure of the Earth.

1860 Jan. 28 On the Claudian or Plautian Invasion of Athenaeum Britain.

1860 Feb. 2 Examination of Navy 2-foot Telescopes at the Royal Observatory, Greenwich, 1860, Jan. 31 to Feb. 2.

1860 Feb. 11 Report on the Instrumental Equipments Ho. of Commons. of the Exchequer Office of Weights and (Parly. Paper.) Measures, as regards the means for preventing Fraud in the Sale of Gas to the Public; and on the Amendments which may be required to the existing Legislation on that subject.

1860 Mar. 9 Address on the approaching Solar Eclipse R. Astr. Soc. of July 18, 1860, &c. (Month. Not.)

1860 May 10 Correspondence between the Lords Ho. of Commons. Commissioners of Her Majesty's Treasury, (Parly. Paper.) &c., and the Astronomer Royal, relating to Gas Measurement, and the Sale of Gas Act.

1860 June 2 Report of the Astronomer Royal to the Board of Visitors. And Address to the Members of the Board in reference to Struve's Geodetic suggestions.

1860 June 7 Correspondence regarding the Grant of £1000 to Prof. Hansen for his Lunar Tables.

1860 Sept. 13 Remarks on a Paper entitled "On the Polar Distances of the Greenwich Transit Circle, by A. Marth." Addressed to the Members of the Board of Visitors.

1860 Sept. 22 On Change of Climate, in answer to Athenaeum. certain speculations by Sir Henry James.

1860 Oct. 20 Circular relating to the distribution of Greenwich Observations and other publications of the Royal Observatory.

1860 Nov. 9 Account of Observations of the Total R. Astr. Soc. Solar Eclipse of 1860, July 18, made (Month. Not.) at Hereña, near Miranda de Ebro; &c. &c.

1860 Nov. 17 On Change of Climate: further discussion. Athenaeum.

1860 Letters on Lighthouses, to the Commission on Lighthouses.

1860 Dec. 14 Note on the translation of a passage in a R. Astr. Soc. letter of Hansen's relating to (Month. Not.) coefficients.

1861 Feb. 9 On the Temperature-correction of Syphon Athenaeum. Barometers.

1861 March Results of Observations of the Solar R. Astr. Soc. Eclipse of 1860 July 18 made at the Royal (Month. Not.) Observatory, Greenwich, for determination of the Errors of the Tabular Elements of the Eclipse. Also Suggestion of a new Astronomical Instrument, for which the name "Orbit-Sweeper" is proposed. Also Theory of the Regulation of a Clock by Galvanic Currents acting on the Pendulum.

1861 June 1 Report of the Astronomer Royal to the Board of Visitors.

1861 June 5 On a supposed Failure of the Calculus of Phil. Mag. Variations.

1861 July Report of a Committee of the R. Soc. on R. Soc.(Proc.) the advisability of re-measuring the Indian Arc of Meridian.

1861 Sept. 21 Lecture at Manchester on the Great Solar Athenaeum. Eclipse of July 18, 1860.

1861 Sept. 21 The same Lecture. London Review.

1861 Oct. Examination Paper for the Sheepshanks Exhibition.

1861 Nov. 1 Translation of Dr Lamont's Paper "On the Phil. Mag. most Advantageous Form of Magnets."

1861 Nov. 8 Note on a Letter received from Hansen on R. Astr. Soc. the Lunar Theory. Also Discussion of (Month. Not.) a Result deduced by Mr D'Abbadie from Observations of the Total Solar Eclipse of 1860, July 18.

1861 Nov. 16 Instructions for observing the Total Eclipse of the Sun on December 31.

1861 Dec. On a Projection by Balance of Errors for Phil. Mag. Maps.

1861 Dec. 28 On the Circularity of the Sun's Disk. R. Astr. Soc. Also Table of Comparative Number of (Month. Not.) Observations of Small Planets.

1862 Jan. On the Direction of the Joints in the Phil. Mag. Faces of Oblique Arches.

1862 Mar. 15 Review of "An Historical Survey of the Athenaeum. Astronomy of the Ancients" by the Rt Hon. Sir G. Cornewall Lewis.

1862 Apr. 24 Notes for the Committee on Weights and Measures, 1862.

1862 May 15 On the Magnetic Properties of Hot-Rolled Phil. Trans. and Cold-Rolled Malleable Iron.

1862 June 7 Report of the Astronomer Royal to the Board of Visitors.

1862 June 24 Evidence given before the Select Committee on Weights and Measures.

1862 Oct. 4 Biography of G.B. Airy (probably in part London Review. based upon data supplied by himself).

1862 Oct. 11 Abstract of Paper "On the Strains in the Athenaeum. Interior of Beams and Tubular Bridges."

1862 Oct. 11 Translation of a Letter from Prof. Lament Phil. Mag. on Dalton's Theory of Vapour, &c.

1862 Nov. 6 On the Strains in the Interior of Beams. Phil. Trans.

1862 Nov. Correspondence with Sabine concerning his attack on the Greenwich Magnetic Observations. (Confidentially communicated to the Board of Visitors.)

1862 Nov. 21 Evidence given before the Public Schools Commission.

1862 Nov. Abstract of M. Auwers's Paper on the R. Astr. Soc. proper motion of Procyon, and Note on (Month. Not.) same.

1862 Dec. Abstract of Mr Safford's Paper on the R. Astr. Soc. Proper Motion of Sirius. Also on the (Month. Not.) Forms of Lenses proper for the Negative Eye-pieces of Telescopes. Also on the measurements of the Earth, and the dimensions of the Solar System. Also on Fringes of Light in Solar Eclipses.

1863 Jan. Address to the Board of Visitors on a further attack by Sabine on the Greenwich Magnetic Observations (confidential).

1863 Jan. 9 On the Observations of Saturn made at R. Astr. Soc. Pulkowa and Greenwich. (Month. Not.)

1863 Feb. 24 Report to the Board of Trade on the Proposed Lines of Railway through Greenwich Park.

1863 Mar. 2 Determination of the Longitude of Valencia in Ireland by Galvanic Signals in the summer of 1862 (App. III. to the Gr. Astr. Obsns. 1862).

1863 Mar. 13 On the Movement of the Solar System in R. Astr. Soc. Space, deduced from the Proper Motions (Memoirs.) of 1167 Stars. By Edwin Dunkin (for G.B.A.).

1863 Mar. 13 On the Visibility of Stars in the Pleiades R. Astr. Soc. to the unarmed eye. (Month. Not.)

1863 Mar. 21 On Marriage Odes. Athenaeum.

1863 Apr. 9 Further Report as to the Probable Effects of the London, Chatham and Dover Railway on the Royal Observatory in Greenwich Park.

1863 Apr. 10 Determination of the Sun's Parallax from R. Astr. Soc. observations of Mars during the (Month. Not.) Opposition of 1862. By E.J. Stone (for G.B.A.). Also Remarks on Struve's account of a Local deviation in the direction of Gravity, near Moscow. Also an Account of an apparatus for the observation of the spectra of stars, and results obtained.

1863 Apr. 23 On the Diurnal Inequalities of Phil. Trans. Terrestrial Magnetism, as deduced from observations made at the Royal Observatory, Greenwich, from 1841 to 1857.

1863 May 8 On the Discordance between the Results R. Astr. Soc. for Zenith-Distances obtained by Direct (Memoirs.) Observation, and those obtained by Observation by Reflection from the Surface of Quicksilver.

1863 June 6 Report of the Astronomer Royal to the Board of Visitors.

1863 July 2 On the Amount of Light given by the R. Astr. Soc. Moon at the greatest stage in the (Month. Not.) Excentrically-total Eclipse, 1863, June 1.

1863 Aug. Plan of the Buildings and Grounds of the Royal Observatory, Greenwich, with Explanation and History.

1863 Sept. 5 On the origin of the apparent luminous R. Astr. Soc. band which, in partial eclipses of the (Month. Not.) Sun, has been seen to surround the visible portion of the Moon's limb.

1863 Sept. 5 On the Invasions of Britain by Julius Athenaeum. 1863 Oct. 3 Caesar.

1863 Oct. 17 The Earthquake as observed from Greenwich. Athenaeum.

1863 Nov. On the Numerical Expression of the Phil. Mag. Destructive Energy in the Explosions of Steam-Boilers, &c.

1863 Nov. 13 Convention arranged between M. Le Verrier R. Astr. Soc. and the Astronomer Royal for meridional (Month. Not.) observations of the small Planets, &c.

1863 Nov. 13 Translation of Hansen's Paper R. Astr. Soc. "Calculation of the Sun's Parallax (Month. Not.) from the Lunar Theory," with Notes by G.B.A.

1863 Dec. 17 First Analysis of 177 Magnetic Storms, Phil. Trans. registered by the Magnetic Instruments in the Royal Observatory, Greenwich, from 1841 to 1857.

1864 Jan. 8 Pontécoulant's Paper "Sur le Coefficiant R. Astr. Soc. de l'Équation Parallactique déduit de la (Month. Not.) Théorie," with Notes by G.B.A.

1864 Jan. 26 Remarks on Redman's Paper on the East Inst. C. E. Coast (Chesil Bank, &c.). (Minutes.)

1864 Mar. 10 Note on a Passage in Capt. R. Astr. Soc. Jacob's "Measures of Jupiter," &c. (Month. Not.)

1864 Mar. 11 Notes for the Committee on Weights and Ho. of Comm. Measures, 1862. (Parly. Paper.)

1864 Mar. 17 On a Method of Slewing a Ship without Inst. Nav. Arch. the aid of the Rudder.

1864 Apr. 5 Comparison of the Chinese Record of Solar R. Astr. Soc. Eclipses in the Chun Tsew with the (Month. Not.) Computations of Modern Theory.

1864 June 4 Report of the Astronomer Royal to the Board of Visitors.

1864 June 10 On the Transit of Venus, 1882, Dec. 6. R. Astr. Soc. (Month. Not.)

1864 June 10 On the bright band bordering the Moon's R. Astr. Soc. Limb in Photographs of Eclipses. (Month. Not.)

1864 Notes on Methods of Reduction applicable to the Indian Survey.

1864 Sept. 3 A Visit to the Corryvreckan. Athenaeum.

1864 Sept. 29 Examination Paper for the Sheepshanks Scholarship.

1865 Jan. 13 Comparison of the Transit-Instrument in R. Astr. Soc. its ordinary or reversible form with the (Month. Not.) Transit-Instrument in its non-reversible form, as adopted at Greenwich, the Cape of Good Hope, and other Observatories.

1865 Mar. 9 Syllabus of a course of three Lectures on "Magnetical Errors, &c., with special reference to Iron Ships and their Compasses," delivered at the South Kensington Museum.

1865 Apr. 1 Remarks on Mr Ellis's Lecture on the Horolog. Journ. Greenwich System of Time Signals.

1865 Apr. 1 Free Translation of some lines of Virgil, Athenaeum. "Citharâ crinitus Iopas," &c.

1865 June 3 Report of the Astronomer Royal to the Board of Visitors.

1865 June 17 Note on my Recommendation (in 1839) Athenaeum. of Government Superintendence of the Compasses of Iron Ships. Also Note on the birthplace of Thomas Clarkson.

1865 July On Hemiopsy. Phil. Mag.

1865 Aug. 22 On the Value of the Moon's Semidiameter R. Astr. Soc. as obtained by the Investigations of (Month. Not.) Hugh Breen, Esq., from Occultations observed at Cambridge and Greenwich.

1865 Sept. 16 On "The Land of Goshen"--Reply to "A Athenaeum. Suffolk Incumbent."

1865 Oct. 21 Address of the Astronomer Royal to the individual members of the Board of Visitors. (On improved Collimators.)

1865 Oct. 23 Note on an Error of Expression in two R. Astr. Soc. previous Memoirs. Also Description and (Month. Not.) History of a Quadrant made by Abraham Sharp.

1865 Nov. 11 On the Possible Derivation of the National Athenaeum. Name "Welsh."

1865 Essays on the Invasion of Britain by Julius Private. Caesar; The Invasion of Britain by Plautius, and by Claudius Caesar; The Early Military Policy of the Romans in Britain; The Battle of Hastings. (With corr.)

1866 Mar. 10 On "The Compass in Iron Ships." Objections Athenaeum. to passages in a Lecture by Archibald Smith.

1866 Apr. 13 On the Supposed Possible Effect of R. Astr. Soc. Friction in the Tides, in influencing the (Month. Not.) Apparent Acceleration of the Moon's Mean Motion in Longitude. Also on a Method of Computing Interpolations to the Second Order without Changes of Algebraic Sign.

1866 June 2 Report of the Astronomer Royal to the Board of Visitors.

1866 July 17 Papers relating to Time Signals on the Ho. of Comm. Start Point. (Parly. Paper.)

1866 Sept. 1 On the Campaign of Aulus Plautius in Athenaeum. Britain. (Reply to Dr Guest.)

1866 Nov. 19 On the Continued Change in an Eye Camb. Phil. Soc. affected with a peculiar malformation.

1866 Dec. On the Simultaneous Disappearance of R. Astr. Soc. Jupiter's Satellites in the year 1867. (Month. Not.) Also Inference from the observed Movement of the Meteors in the appearance of 1866, Nov. 13-14.

1867 Jan. 1 Memorandum for the consideration of the Commission on Standards. (Policy of introducing Metrical Standards.)

1867 Jan. 12 On Decimal Weights and Measures. Athenaeum.

1867 Feb. 19 On the use of the Suspension Bridge with Inst. C.E. Stiffened Roadway for Railway and other (Minutes.) Bridges of Great Span.

1867 Mar. 21 Computation of the Lengths of the Waves Phil. Trans. of Light corresponding to the Lines in the Dispersion Spectrum measured by Kirchhoff.

1867 Mar. Corresponding Numbers of Elevation in R. Obs. (Also English Feet, and of Readings of Aneroid Meteor. Soc. or Corrected Barometer in English Apr. 17, 1867.) Inches.

1867 Apr. 16 Remarks on Sir W. Denison's Paper on Inst. C.E. "The Suez Canal." (Minutes.)

1867 May 3 Statement of the History and Position of Private. the Blue-coat Girls' School, Greenwich.

1867 June 1 Report of the Astronomer Royal to the Board of Visitors.

1867 June 14 On Certain Appearances of the Telescopic R. Astr. Soc. Images of Stars described by the Rev. (Month. Not.) W.R. Dawes.

1867 Dec. 13 Note on the Total Solar Eclipse of 1868, R. Astr. Soc. Aug. 17-18. (Month. Not.)

1868 Biography of G.B. Airy. (Probably corrected by himself.)

1868 Jan. 4 Biography (with portrait) of G.B. Airy. Ill. Lond. News. (Probably corrected by himself.)

1868 Feb. 6 Comparison of Magnetic Disturbances Phil. Trans. recorded by the Self-registering Magnetometers at the Royal Observatory, Greenwich, with Magnetic Disturbances deduced from the corresponding Terrestrial Galvanic Currents recorded by the Self-registering Galvanometers of the Royal Observatory.

1868 Mar. 13 Address of the Astronomer Royal to the Individual Members of the Board of Visitors. (Number of Copies of Observations.)

1868 June 6 Report of the Astronomer Royal to the Board of Visitors.

1868 July 24 First Report of the Commissioners appointed Parly. Paper. to enquire into The Condition of the Exchequer Standards.

1868 Sept. 19 The Inundation at Visp. Athenaeum.

1868 Nov. 9 On the Factorial Resolution of the Trinomial Camb. Phil. Soc. x^n - 2cos n. a. + 1/x^n.

1868 Dec. 10 On the Diurnal and Annual Inequalities Phil. Trans. of Terrestrial Magnetism, as deduced from Observations made at the Royal Observatory from 1858 to 1863, &c.

1868 Dec.11 On the Preparatory Arrangements for the R. Astr. Soc. Observation of The Transits of Venus (Month. Not.) 1874 and 1882.

1868 Dec. 12 On the Migrations of the Welsh Nations. Athenaeum.

1869 Mar. 8 Memorandum by the Chairman (on the use of the Troy Weight) for the consideration of the Members of the Standards Commission.

1869 Apr. 3 Second Report of the Commissioners appointed Parly. Paper. to enquire into the condition of the Exchequer (now Board of Trade) Standards.--The Metric System.

1869 April Syllabus of Lectures on Magnetism to be delivered in the University of Cambridge.

1869 Apr. 27 Remarks on Shelford's Paper "On the Inst. C.E. Outfall of the River Humber." (Minutes.)

1869 June 1 Memorandum for the consideration of the Standards Commission, on the state of the Question now before them regarding the suggested Abolition of Troy Weight.

1869 June 5 Report of the Astronomer Royal to the Board of Visitors.

1869 Supplementary Memorandum by the Astronomer Royal on the proposed Abolition of Troy Weight.

1869 July 6 Correspondence between the Treasury, the Ho. of Comm. Admiralty, and the Astronomer Royal, (Parly. Paper.) respecting the arrangements to be made for Observing the Transits of Venus, which will take place in the years 1874 and 1882.

1869 Aug. 7 Note on Atmospheric Chromatic Dispersion R. Astr. Soc. as affecting Telescopic Observation, and (Month. Not.) on the Mode of Correcting it.

1869 Oct. 19 Description of the Great Equatoreal of the Royal Observatory, Greenwich. Greenwich Observations, 1868. App.

1870 Feb. 3 Note on an Extension of the Comparison Phil. Trans. of Magnetic Disturbances with Magnetic Effects inferred from observed Terrestrial Galvanic Currents; &c. &c.

1870 Apr. 8 On the question of a Royal Commission Journ. Soc. Arts. for Science.

1870 May 2 Letters to the First Lord of the Admiralty enclosing Application of the Assistants for an increase of Salaries.

1870 May 13 On Decimal and Metrical Systems. Journ. Soc. Arts.

1870 June 4 Report of the Astronomer Royal to the Board of Visitors.

1870 Aug. 27 On the meaning of the word "Whippultree." Athenaeum.

1870 Oct. 22 On the Locality of "Paradise." Athenaeum.

1870 Nov. 12 On the Locality of the Roman Gesoriacum. Athenaeum.

1870 Nov. 30 Recommendation of Prof. Miller for a R. Soc.(Proc.) Royal Medal of the Royal Society. (Quoted by the President.)

1870 Revised Edition of "Astronomy." Man. Naut. Sci.

1871 Jan. 21 The Burial of Sir John Moore. Athenaeum.

1871 Mar. 14 Letter to the Hydrographer of the Admiralty on the qualifications and claims of the Assistants of the Royal Observatory.

1871 Apr. 5 Remarks on the Determination of a Ship's R. Soc. (Proc.) Place at Sea.

1871 May 2 Remarks on Samuelson's Paper "Description Inst. C.E. of two Blast Furnaces," &c. (Minutes.)

1871 May 3 Note on Barometric Compensation of the Phil. Mag. Pendulum.

1871 June 3 Report of the Astronomer Royal to the Board of Visitors.

1871 June 9 Remarks on Mr Abbott's observations on R. Astr. Soc. eta Argûs. Also on A.S. Herschel's and (Month. Not.) J. Herschel's Mechanism for measuring Time automatically in taking Transits.

1871 Erratum in Results of Greenwich R. Astr. Soc. Observations of the Solar Eclipse of 1860, (Month. Not.) July 18. Also Observations of the Solar Eclipse of 1870, Dec. 21-22, made at the Royal Observatory, Greenwich.

1871 Aug. Investigation of the Law of the Progress Phil. Mag. of Accuracy in the usual process for Forming a Plane Surface.

1871 Nov.16 Corrections to the Computed Lengths of Phil. Trans. Waves of Light for Kirchhoff's Spectral Lines.

1871 On a supposed alteration in the amount R. Soc. (Proc.) of Astronomical Aberration of Light, produced by the passage of the Light through a considerable thickness of Refracting Medium.

1871 Nov. 29 Biography of G.B. Airy. (Probably Daily Telegraph. corrected by himself.)

1871 Dec. 8 Note on a special point in the R. Astr. Soc. determination of the Elements of the (Month. Not.) Moon's Orbit from Meridional Observations of the Moon.

1871 Dec. 26 Proposed devotion of an Observatory to R. Astr. Soc. observation of the phenomena of Jupiter's (Month. Not.) Satellites.

1872 Jan. Address to the Council of the Royal Society on the propriety of continuing the Grant to the Kew Observatory for meteorological observations.

1872 Feb. 8 Experiments on the Directive Power of Phil. Trans. large Steel Magnets, of Bars of magnetized Soft Iron, and of Galvanic Coils, in their Action on external small Magnets--with Appendix by James Stuart.

1872 Feb. 12 Further Observations on the state of an Camb. Phil. Soc. Eye affected with a peculiar malformation.

1872 Mar. 20 Notes on Scientific Education, submitted to the Royal Commission on Scientific Instruction and the Advancement of Science.

1872 May 9 On a Supposed Periodicity in the R. Soc. (Proc.) Elements of Terrestrial Magnetism, with a period of 26-1/4 days.

1872 Nov. 30 Address (as President) delivered at the Anniversary Meeting of the Royal Society.

1872 Dec. 19 Magnetical Observations in the Phil. Trans. Britannia and Conway Tubular Iron Bridges.

1873 Feb. 25 Remarks on Mr Thornton's Paper on Inst. C.E. "The State Railways of (Minutes.) India"--chiefly in reference to the proposed break of gauge.

1873 Mar. 12 Note on the want of Observations of R. Astr. Soc. Eclipses of Jupiter's First Satellite (Month. Not.) from 1868 to 1872.

1873 Mar. 14 Letter to the Secretary of the R. Astr. Soc. Admiralty on certain Articles which (Month. Not.) had appeared in the Public Newspapers in regard to the approaching Transit of Venus.

1873 Additional Note to the Paper on a R. Soc. (Proc.) supposed Alteration in the Amount of Astronomical Aberration of Light produced by the passage of the Light through a considerable thickness of Refracting Medium.

1873 Apr. 10 List of Candidates for election into the Royal Society--classified.

1873 On the Topography of the "Lady of Private. the Lake."

1873 June 7 Report of the Astronomer Royal to the Board of Visitors.

1873 Nov. 14 On the rejection, in the Lunar R. Astr. Soc. Theory, of the term of Longitude (Month. Not.) depending for argument on eight times the mean longitude of Venus minus thirteen times the mean longitude of the Earth, introduced by Prof. Hansen; &c.

1873 Dec. 1 Address (as President) delivered at the Anniversary Meeting of the Royal Society.

1874 Jan. On a Proposed New Method of treating R. Astr. Soc. the Lunar Theory. (Month. Not.)

1874 May 4 British Expeditions for the Observation of the Transit of Venus, 1874, December 8. Instructions to Observers.

1874 June 6 Report of the Astronomer Royal to the Board of Visitors.

1874 Aug. 6 Regulations of the Royal Observatory, Greenwich. Appendix to the Greenwich Observations, 1873.

1874 Oct. 3 Science and Art. The Moon as carved Athenaeum. on Lee church.

1874 Nov. 13 Preparations for the Observation of the R. Astr. Soc. Transit of Venus 1874, December 8-9. (Month. Not.)

1874 Nov. 17 Remarks on the Paper "On the Nagpur Inst. C.E. Waterworks." (Minutes.)

1874 Dec. Telegrams relating to the Observations R. Astr. Soc. of the Transit of Venus 1874, Dec. 9. (Month. Not.)

1875 Feb. 2 Remarks on Mr Prestwich's Paper on the Inst. C.E. Origin of the Chesil Bank. (Minutes.)

1875 Feb 25 Letter to the Rev. N. M. Ferrers, on the subject of the Smith's Prizes.

1875 Mar. 12 On the Method to be used in Reducing R. Astr. Soc. the Observations of the Transit of (Month. Not.) Venus 1874, Dec. 8.

1875 Mar. Report on the Progress made in the R. Astr. Soc. Calculations for a New Method of (Month. Not.) treating the Lunar Theory.

1875 June 5 Report of the Astronomer Royal to the Board of Visitors.

1875 June 7 Apparatus for Final Adjustment of the Horolog. Journ. Thermal Compensation of Chronometers, by the Astronomer Royal.

1875 Nov. Chart of the Apparent Path of Mars, 1877, R. Astr. Soc. with neighbouring Stars. Also (Month. Not.) Spectroscopic Observations made at the Royal Observatory, Greenwich. Also Observations of the Solar Eclipse of 1875, September 28-29, made at the Royal Observatory, Greenwich.

1876 Jan. Report by the Astronomer Royal on the R. Astr. Soc. present state of the Calculations in his (Month. Not.) New Lunar Theory.

1876 Jan. 27 Note on a point in the life of Sir William Athenaeum. Herschel.

1876 Mar. 15 Evidence given before the Government Committee on the Meteorological Committee.

1876 May 20 On Toasting at Public Dinners. Public Opinion.

1876 June 3 Report of the Astronomer Royal to the Board of Visitors,

1876 Aug. 7 On a Speech attributed to Nelson. Athenaeum.

1876 Dec. Spectroscopic Results for the Rotation of R. Astr. Soc. Jupiter and of the Sun, obtained at the (Month. Not.) Royal Observatory, Greenwich.

1877 Jan. Stars to be compared in R.A. with Mars, R. Astr. Soc. 1877, for Determination of the Parallax (Month. Not.) of Mars.

1877 Mar. Note by the Astronomer Royal on the R. Astr. Soc. Numerical Lunar Theory. Also Remarks (Month. Not.) on Le Verrier's intra-Mercurial Planet. Also on Observations for the Parallax of Mars.

1877 Mar. 27 Remarks on a Paper on "The River Inst. C.E. Thames." (Minutes.)

1877 Apr. On observing for Le Verrier's intra-Mercurial R. Astr. Soc. Planet. Also on the Parallax of (Month. Not.) Mars, and Mr Gill's proposed expedition.

1877 May On the vulgar notion that the Sun or Moon The Observatory is smallest when overhead. (No. 2).

1877 June 2 Report of the Astronomer Royal to the Board of Visitors.

1877 July 16 Report on the Telescopic Observations of Ho. of Commons the Transit of Venus 1874, made in the Parly. Paper. Expedition of the British Government, and on the Conclusion derived from those Observations.

1877 Sept. 13 On Spurious Discs of Stars produced by The Observatory oval object-glasses. (No. 7).

1877 Sept. 24 Obituary Notice of the work of Le Daily News. Verrier--died Sept. 23, 1877.

1877 Nov. 20 On the Value of the Mean Solar Parallax The Observatory &c. from the British telescopic Observations (No. 8). of the Transit of Venus 1874. Also Remarks on Prof. Adams's Lunar Theory.

1877 Nov. On the Inferences for the Value of Mean R. Astr. Soc. Solar Parallax &c. from the Telescopic (Month. Not.) Observations of the Transit of Venus 1874, which were made in the British Expedition for the Observation of that Transit.

1877 Numerical Lunar Theory: Appendix to Greenwich Astronomical Observations 1875.

1877 Dec. 6 On the Tides at Malta. Phil. Trans.

1878 Correspondence with Le Verrier on his The Observatory Planetary Tables in 1876. (No. 10).

1878 On the Proposal of the French Committee The Observatory to erect a Statue to Le Verrier. Also (No. 13). on the Observation of the approaching Transit of Mercury.

1878 Mar. 11 On the Correction of the Compass in Phil. Mag. Iron Ships without use of a Fixed Mark.

1878 Mar. 30 On the Standards of Length in the The Times. Guildhall, London.

1878 Apr. 27 Report of Lecture on "The probable W. Cumberland condition of the Interior of the Times. Earth." On the probable condition of the Trans. of the Interior of the Earth--Revised Cumberland Edition of above Lecture. Assoc., &c.

1878 June 1 Discussion of the Observations of The Observatory the Transit of Mercury on May 6. (No. 14).

1878 Abstract of Lecture delivered at The Observatory Cockermouth on "The Interior of the (No. 14). Earth."

1978 June 1 Report of the Astronomer Royal to the Board of Visitors.

1878 July 1 Remarks on the measurement of the The Observatory photographs taken in the Transit of (No. 15). Venus Observations.

1878 July 13 On the Variable Star R. Scuti: The Observatory distortion in the Photo-heliograph. (No. 16).

1878 Remarks on Mr Gill's Heliometric The Observatory Observations of Mars. (No. 20).

1878 Dec. Note on a Determination of the Mass R. Astr. Soc. of Mars, and reference to his own (Month. Not.) determination in 1828. Also Note on the Conjunction of Mars and Saturn, 1879, June 30.

1879 Jan. 1 On the remarkable conjunction of The Observatory the Planets Mars and Saturn which (No. 21). will occur on 1879, June 30.

1879 Feb. 15 On the names "Cabul" and "Malek." Athenaeum

1879 Feb. 25 On Faggot Votes in Cornwall in 1828. Athenaeum

1879 Mar. 13 Letter on the Examination Papers for the Smith's Prizes.

1879 Apr. 7 Drafts of Resolutions proposed concerning Sadler's Notes on the late Admiral Smyth's "Cycle of Celestial Objects."

1879 June 1 Letter to Le Verrier, dated 1875, The Observatory Feb. 5, in support of the Method (No. 26). of Least Squares.

1879 June 1 Remarks in debate on Sadler's The Observatory "Notes" above-mentioned. (No. 26).

1879 June 7 Report of the Astronomer Royal to the Board of Visitors.

1879 July 29 Index to the Records of occasional R. Astr. Soc. Observations and Calculations made (Month. Not. at the Royal Observatory, Greenwich, supplementary.) and to other miscellaneous Papers connected with that Institution.

1879 Biography of G. B. Airy (perhaps corrected by himself) in French, published at Geneva.

1879 Sept. On the Construction and Use of a Phil. Mag. Scale for Gauging Cylindrical Measures of Capacity.

1880 On the Theoretical Value of the The Observatory Acceleration of the Moon's Mean (No. 37). Motion.

1880 On the Secular Acceleration of The Observatory the Moon--additional note. (No. 37).

1880 Apr. 27 Memoranda for the Commission appointed to consider the Tay Bridge casualty.

1880 Apr. On the Theoretical Value of the R. Astr. Soc. Acceleration of the Moon's Mean (Month. Not.) Motion in Longitude produced by the Change of Eccentricity of the Earth's Orbit.

1880 May On the Preparations to be made for R. Astr. Soc. Observation of the Transit of Venus (Month. Not.) 1882, Dec. 6.

1880 On the present Proximity of Jupiter The Observatory to the Earth, and on the Intervals of (No. 42). Recurrence of the same Phaenomena.

1880 June 5 Report of the Astronomer Royal to the Board of Visitors.

1880 Sept. 4 On the e muet in French. Athenaeum.

1880 Sept. 4 Excursions in the Keswick Keswick District. Guardian.

1880 Dec. 1 Description of Flamsteed's The Observatory Equatoreal Sextant, and Remarks on (No. 44). Graham.

1880 Addition to a Paper entitled "On R. Astr. Soc. the Theoretical Value of the Moon's (Month. Not. Mean Motion in Longitude," &c. supplementary.)

1881 Mar. Effect on the Moon's Movement in R. Astr. Soc. Latitude, produced by the slow (Month. Not.) change of Position of the Plane of the Ecliptic.

1881 June 4 Report of the Astronomer Royal to the Board of Visitors.

1881 Logarithms of the Values of all Inst. C. E. Vulgar Fractions with Numerator and (Minutes.) Denominator not exceeding 100: arranged in order of magnitude.

1881 July 6 A New Method of Clearing the Lunar Distance.--Admiralty.

1881 Aug. 4 On a Systematic Interruption in the order Phil. Mag. of numerical values of Vulgar Fractions, when arranged in a series of consecutive magnitudes.

1882 Sept. 15 Monthly Means of the Highest and R. Soc. (Proc.) Lowest Diurnal Temperatures of the Water of the Thames, and Comparison with the corresponding Temperatures of the Air at the Royal Observatory, Greenwich.

1882 Oct. 19 On the Proposed Forth Bridge. Nature.

1882 Dec. 7 On the Proposed Forth Bridge. Nature.

1883 Jan. 21 On the Ossianic Poems. Athenaeum.

1883 Mar. 12 On the proposed Braithwaite and Daily News. Buttermere Railway. Times. Standard.

1883 Apr. 28 Memorandum on the progress of the Numerical Lunar Theory, addressed to the Board of Visitors of the Royal Observatory, Greenwich.

1883 Letter on The Apparent Inequality in the The Observatory Mean Motion of the Moon. (No. 74).

1883 Aug. 18 On a Singular Morning Dream. Nature.

1883 Sept. 10 Power of organization of the common Nature. mouse.

1883 Nov. 17 On Chepstow Railway Bridge, with general Nature. remarks suggested by that Structure.

1884 Mar. 8 On the Erroneous Usage of the term Athenaeum. "arterial drainage."

1884 On the Comparison of Reversible and The Observatory Non-reversible Transit Instruments. (No. 85).

1884 Nov. 10 On an obscure passage in the Koran. Nature. (?)

1885 May 28 An Incident in the History of Trinity Athenaeum. College, Cambridge.

1885 June 8 Incident No. 2 in the History of Trinity Athenaeum. College, Cambridge.

1885 Nov. 26 Results deduced from the Measure of Phil. Trans. Terrestrial Magnetic Force in the Horizontal Plane, at the Royal Observatory, Greenwich, from 1841 to 1876.

1886 Apr. 6 Integer Members of the First Centenary Nature. satisfying the Equation A² = B² + C².

1887 Feb. 12 On the earlier Tripos of the University of Nature. (?) Cambridge: in MSS.

1887 Apr. 14 On the Establishment of the Roman Dominion Nature. in South-East Britain.

1887 July 23 On a special Algebraic function, and its Camb. Phil. Soc. application to the solution of (?) some Equations: in MSS.

BOOKS WRITTEN BY G. B. AIRY.

Mathematical Tracts on Physical Astronomy, the Figure of the Earth, Precession and Nutation, and The Calculus of Variations. This was published in 1826. In a 2nd Edition published in 1831 the Undulatory Theory of Optics was added to the above list. Four Editions of this work have been published, the last in 1858. The Undulatory Theory of Optics was published separately in 1877.

Gravitation: an Elementary Explanation of the Principal Perturbations in the Solar System. Written for the Penny Cyclopaedia, and published previously as a book in 1834. There was a 2nd Edition in 1884.

Trigonometry. This was written for the Encyclopaedia Metropolitana about 1825, and was published as a separate book in 1855 under the Title of "A Treatise on Trigonometry."

Six Lectures on Astronomy delivered at the meetings of the friends of the Ipswich Museum at the Temperance Hall, Ipswich, in the month of March 1848. These Lectures under the above Title, and that of "Popular Astronomy, a series of Lectures," have run through twelve editions.

On the Algebraical and Numerical Theory of Errors of Observations and the Combination of Observations, 1st Edition in 1861, 2nd in 1875, 3rd in 1879.

Essays on the Invasion of Britain by Julius Caesar; The Invasion of Britain by Plautius, and by Claudius Caesar; The Early Military Policy of the Romans in Britain; The Battle of Hastings, with Correspondence. Collected and printed for private distribution in 1865.

An Elementary Treatise on Partial Differential Equations. 1866.

On Sound and Atmospheric Vibrations, with the Mathematical Elements of Music. The 1st Edition in 1868, the 2nd in 1871.

A Treatise on Magnetism, published in 1870.

Notes on the Earlier Hebrew Scriptures, published in 1876.

Numerical Lunar Theory, published in 1886.

INDEX.

Accidents (see also Illnesses) Accounts Acts and Opponencies Adams, Prof. J.C. Adams, John Quincey Agrarian fires Aiken Airy, William, father of G.B.A. Airy, Ann, mother of G.B.A. Airy, William, brother of G.B.A., and Basil R. Airy, his son Airy, Arthur, brother of G.B.A. Airy, Elizabeth, sister of G.B.A. Airy, Richarda, wife of G.B.A. Airy, children of G.B.A. George Richard Elizabeth Arthur Wilfrid Hubert Hilda Christabel Annot Osmund Allsop Alnwick Altazimuth instrument Althorp, Lord American Observatories American method of recording Observations (see Galvanic Registration) Ampère Ancient eclipses Anderson, lessee of Harton Colliery Anemometer (see Meteorology) Anniversary parties Antiquarian researches and notes Arago Architecture (see Cathedrals, &c.) Astronomical Society (see Royal Astr. Soc.) Astronomische Gesellschaft Athenaeum newspaper Athenaeum Club Atkinson, Senior Wrangler 1821 Atlantic cable Atmospheric railway (see Railways) Auckland, Lord Aurora Borealis Australian Observatories (see also Observatories) Auwers, Dr Babbage, Charles Baily, Francis Bakhuysen, of Leyden Balance (Public Balance) Baldock, Commander Baldrey, assistant Banks, optician Baring, Sir T. Barlow, Prof. Barlow, W.H. Barnard, Proctor Barnes, Miss Barnes, Gorell Barometers Barry, Sir C. Barton, Bernard Baxter, secretary to the Admiralty Beacons, floating Beaufort, Captain Beaumont's Observatory Bedingfield, pupil Bell Scholarships (see Examinations) Bessell, astronomer Biddell, Arthur, uncle of G.B.A. Biddell, George, uncle of G.B.A. Biddell, William, uncle of G.B.A. Biddell, George Arthur, son of Arthur Biddell Biographical notes Bissett, pupil Blackwood, Captain Blakesley, Canon Blasting Bliss's observations Blomfield, G.B., pupil Bloomfield, Lord Board of Longitude Boileau Bond, G.P. Books, written by G.B.A., Appendix Book Society, Cambr. Bosanquet Bouch, T. Civ. Eng. Boundary of Canada (see Canada) Bouvard, E. Bowstead Bradley's observations Brazil, Emperor of Breakwaters (see Harbours) Breen, assistant Brewster, Sir D. Bridges Brinkley, Dr Bristow, Miss Britannia Bridge (see Bridges) Brooke, Charles British Association Brougham, Lord Browne, G.A. Brunel, Civ. Eng. Buck Buckland, Dr Buckle, pupil Burgoyne, Sir J. Burlington, Lord Burton Busts (see Portraits) Calculating machines Calvert Cambridge Observatory: Assistants Instruments Printed observations General Cambridge University Cambridge Observatory, U.S.A. Canada boundary Cankrein, pupil Canning, Lord Cape of Good Hope, Observatory and Survey Carpenter, assistant Cartmell, Dr Case Catalogues of stars (see Stars) Cathedrals and churches Catton Cavendish experiment Cayley, Prof. Challis, Prof. Chalmers, Dr Cherbourg (see Harbours) Chesil Bank Childers Childers, First Lord of Admiralty Christchurch Christie, Prof. Christie, Astronomer Royal Chronographic barrel (see Galvanic Registration) Chronometers Churches (see Cathedrals) Church service Cincinnati Observatory Clarendon, Lord Clark, Latimer Clarkson, Thomas, and Mrs Clarkson Cleasby, pupil Clegg Clinton, pupil Clocks Cockburn, Sir G. Coinage (see Decimal Coinage) Colby, Col. Colchester Colenso, Bishop College Hall Collorado, Count Colonial Observatories (see Observatories) Comets Commissions Compass corrections Cookson, Dr Cooper, pupil Cooper's telescope (see Telescopes) Copying press Corbaux, Miss Corryvreckan whirlpool Courtney, Rev. J. Cowper, First Commissioner of Works Crawford, pupil Criswick, assistant Cropley, Crosse, Rev. E. Cubitt, Sir W. Daguerrotypes Dalhousie, Lord Davy, Sir Humphrey Davy, Dr Daynou, Lieut. Deal time ball De Berg Decimal coinage and decimal subdividing Dee navigation (see Rivers) Degrees (see also Orders and Elections to Societies) Deighton, publisher De La Rive De La Rue De Launay Deluge, The De Morgan, A. Denison, E.B. Denison, Sir W. Denison, H. Denmark, King of Dent, clockmaker Dent-dale Devonshire, Duke of Dobbs, pupil Dobree, lecturer Docks (see Harbours) Dolcoath experiments Dollond, instrument maker Drainage Drinkwater, Bethune Double-image micrometer Douglas, Sir H. Dover (see Harbours) Dublin professorship (see Professorships) Dublin Observatory (see Observatories) Duë, Baron Dundas, Admiral Dundonald, Lord Dunkin, assistant Dunlop, astronomer Durham observatory Earnshaw Earth currents Eastons, manufacturers Eclipses (see also Ancient Eclipses) Edinburgh Observatory Edmonston, Dr Education (see University Education) Egyptian Astronomical Tablets Elections to societies, &c. (see also Degrees and Orders) Electricity, atmospheric Ellenborough, Lord Ellis, W., assistant Elphinstone Encke and Encke's Comet Encyclopaedia Metropolitana Engines (see Steam-engines) Equatoreal, large Estcourt, Col. Evans, lecturer Examinations Exhibitions and prizes Exodus of the Israelites Eye, defects of Eye, estate at Fallows, astronomer Faraday Farish Farr Fellowship Field Fisher Fishmongers' Company Fletcher, Isaac, M.P. Floating Island, Derwentwater Fluid telescope, Barlow's Foley Forbes, Prof. J.D. Foster, Messrs Fox, Alfred Freedom of the City of London Freemantle, Sir T. French, Dr Friends, Personal friends at Cambridge Fries, Prof. Galbraith Galle Galvanic communication, Time-signals, Clocks, and Registration (see also Earth currents) Gambard Gas Act Gauss Gautier Geodesy Geology Geological Society Germany Gibson, pupil Gilbert, Messrs Gilbert, Davies Gill, astronomer Gladstone, W.E. Glaisher, assistant Glasgow Observatory Gordon Gosset Goulburn, Chancellor of the Exchequer Gould, Dr B.A. Goussel Graduation of circles Grant, of Glenmoriston Great Circle sailing (see Navigation) Great Eastern (see Ships) Great Exhibition Great Gable Green, Commander U.S.N. Greenwich Greenwich Observatory, before his appointment as Astronomer Royal Greenwich Observatory: Appointment as Astronomer Royal, and subsequently as Visitor Buildings and grounds in, Instruments Assistants Computations Papers and manuscripts (arrangement of) Estimates Printed Observations Visitations and Reports General Gresswell Groombridge's Catalogue (see Stars) Guest, Caius College Haarlem Hall, Col. Halley and Halley's Comet Hamilton Hamilton, Sir W.R. Hamilton, Admiral Hansard Hansen, Prof. Hansteen Harbours Harcourt, Rev. W. Vernon Hartnup, astronomer Harton Colliery experiments Haviland, Dr Hawkes, Trinity College Hebrew Scriptures Heliograph Hencke Henderson, astronomer Henslow, Prof. Herbert, G. Hereford Herschel, Sir John Herschel, Miss Caroline Herschel, Col. J. Hervey, pupil Higman, Tutor, Trinity College Hilgard, U.S.A. Himalaya Expedition Hind, Moderator Hind, Superintendent Nautical Almanac Hopkins Hovenden, pupil Hudson Huggins, Dr Humboldt, Baron A. Humphreys Hussey, Dr Hustler, Tutor, Trinity College Hyde Parker, Admiral Hygrometers Ibbotson, pupil Iliff Illnesses Inequality, Venus and Earth Inglis, Sir R. Institut de France Institution of Civil Engineers Inverness, Northern Institution of Ipswich Lectures Ireland, notes of Ivory Jackson Jackson, John James, Sir H. Janus (see Steam-engines) Jarrow (see Harbours) Jeffries Jerrard, Dr Jervis, Major Jeune, Dr, V.C. of Oxford Johnson, Capt. Johnson, astronomer Jones, instrument-makers Jones, R. Journeys: Scotland and Cumberland; Swansea; Derbyshire, &c.; Wales; Keswick, &c.; Cornwall, &c.; Orléans; Lake District, &c.; Continent, Observatories, &c.; Cornwall, &c.; Derbyshire; Oxford &c.; Cumberland; Ireland; Scotland; Derbyshire, &c.; Cumberland, &c.; Ireland; Kent; S. Wales; Luddington and Yorkshire; Border of Scotland; S. Wales; Cumberland and Yorkshire; South of Ireland; Ireland; France; Cornwall; Germany; Petersburg, &c.; Ireland; Shetland; Scotland; Sweden; Madeira; Cumberland; Cumberland; Oban, &c.; Italy and Sicily; West Highlands; Switzerland; Central France; Spain (eclipse); Cumberland; West Highlands; West Highlands; Cumberland; Norway; Cumberland; Switzerland; Cumberland; Cumberland; Cumberland; Scotland; Scotland; N. of Scotland; Ireland; Scotland, &c.; Cumberland; Cumberland; Cumberland; Cumberland; S. Wales; Cumberland 358; Cumberland Julius Caesar, landing of Jupiter (see Planets) Keeling Kennedy King, Joshua Kingstown Knight, publisher Knighthood, offers of Lagarde Laing Landman, Engineer Langton Lardner, Dr Lassell, and Lassell's telescope Latitude determinations Lax, Prof. Lectures: College Professorial Miscellaneous Lefevre, J.G.S. Leitch, Dr Le Verrier Lewis, H. Lewis, Sir G.C. Lightfoot, Rev. Dr Lighthouses Lightning Lillingstone Lindsay, Lord Listing, Prof. Liverpool Observatory Livingstone, Dr Lloyd, Dr Lloyd, Prof. Lockyer Lodge London University London, Freedom of the City Long vacations, with pupils Longitude determinations Longitude, Board of (see Board of Longitude) Lowe, Chancellor of the Exchequer Lubbock, Sir John Lucas (computer) Lucasian Professorship (see Professorships) Lunar Reductions Lunar Theory and Tables (see also Numerical Lunar Theory) Lyndhurst, Lord Lyons, Sir E. Macaulay, T.B. Macdonnell, Dr Maclean, of Loch Buy Maclear, Astronomer Madras Observatory 101 Magnetic Observatory and Magnetism (see also Meteorology, Compass corrections, and Earth currents) Main, Robert Maine Boundary (see Canada) Maiden, Prof. Malkin Malta Man-Engines (see Mines) Manuscripts (see Papers) Mars (see Planets) Marshman, pupil Marth, A. Martin, Trin. Coll. Maskelyne, astronomer Mason Mathematical Investigations (see also Appendix "Printed Papers") Mathematical Tracts Mathematical subjects in Maudslays and Field May, Ransomes and May Medals Melbourne University Melville, Lord Mercury (see Planets) Merivale, Dr Meteorology Meteors Middleton, Sir W. Milaud Military researches Miller, Prof. Mines Minto, Lord Mitchell, astronomer Mitchell Miss Molesworth, Sir W. Monteagle, Lord Monument in Playford church Moon: Observations of Theory and Tables of (see Lunar Theory and Tables) Reductions of Observations of (see Lunar Reductions) Mass of Morpeth, Lord Morton, Pierce, pupil Murchison, Sir R. Murray, publisher Musgrave, Charles Musgrave, T. Archbishop Myers Nasmyth Nautical Almanac Navigation Neate, pupil Neptune and Uranus Newall Newcombe, Prof. New Forest Northampton, Lord Northumberland Telescope Numerical Lunar Theory Observatories: see American, Australian, Beaumont's, Cambridge, Cambridge U.S.A., Cape of Good Hope, Cincinnati, Colonial, Dublin, Durham, Edinburgh, Glasgow, Greenwich, Liverpool, Madras, Oxford, Paris, Paramatta, Pulkowa, St Helena, Williamstown Occultations O'Connell Ogilby, pupil Oppolzer, Prof. Opponencies (see Acts and Opponencies) Optics Orders (see also Degrees and Elections to Societies) Ouvaroff, Count Oxford Observatory Oxford, Miscellaneous Packington, Sir J. Palmerston, Lord Papers (see Appendix "Printed Papers") Papers, Arrangement of Parachute, Fall of Parallax (see Sun) Paramatta Observatory Parker, Charles Parker, Vice-Chancellor Paris, Dr Paris Observatory Paris Exhibition Parliamentary Elections Pasley Paul Peacock, George Pearson, Dr Peel, Sir Robert Pendulum Investigations and Experiments Penny Cyclopaedia Pension Pentland Percy, Bishop Personal sketch Philosophical Society, Cambridge Philpott, Dr Photography Piers (see Harbours) Pinheiro, Lieut. Pipon, Lieut. Plana, astronomer Planetary influences Planetary Reductions Planets (see also Transits of Venus) Plantamour Playford Plumian Professorship (see Professorships) Pocket-books for Observations Pogson, astronomer Pond, astronomer Portlock, Capt. Portraits, busts, &c. Post Office, (clocks, &c.) Post Office, stamps and envelopes Pouillet Prince Albert Pritchard, Rev. C. Prizes (see Exhibitions) Probable errors Professorships: Dublin; Lucasian; Plumian Public Schools Commission Pulkowa Observatory Pupils: Bedingfield; Bissett; Blomfield; Buckle; Cankrein; Cleasby; Clinton; Cooper; Crawford; Dobbs; Gibson; Guest; Hervey; Hovenden; Ibbotson; Lewis; Marshman; Morton; Neate; Ogilby; Parker; Rosser; Smith; Tinkler; Tottenham; Turner; Wigram; Williamson Pym, Engineer Queen, H.M. the Queen, Quéroualle, Mdlle de Quetelet Railways, near Observatory Railway Gauge Commission Railways, miscellaneous Rain (see Meteorology) Rainbows Ransomes, also Ransomes and May 17, Reach Reflex zenith tube Religious tests and views Repsold Rhodes Richardson, assistant Rigaud, Prof. Rivers Robinson, Dr Robinson, Capt. Rogers, Rev. Rogers, school assistant Romilly, Lord Ronalds Rose, Rev. H.J. Rosse, Lord, and Rosse's Telescope Rosser, pupil Rothery Rothman Round Down Cliff, blasting of Rouse, Rev. R.C. M. Routh, Dr E.J. Royal Astronomical Society (see also Appendix "Printed Papers") Royal Exchange clock Royal Institution Royal Society (see also Appendix "Printed Papers") Royal Society of Edinburgh Rüncker, Paramatta Rüncker Rundell Rusby Russell, Lord John Sabine, Col. Sadler, H. Saint Helena Observatory Samuda Saturn (see Planets) Saunders, G.W. By Saw-mills (see Ship timbers) Schehallien, mountain Scholarship Scholefield Schumacher Scientific Manual Scoop-wheels Scoresby, Dr Scriptural Researches (see Hebrew Scriptures) Sedgwick, Adam Selwyn, Prof. Senate House Examination (see also University Education) Sewers Commission Sheepshanks, Rev. Richard, and Miss Sheepshanks Sheepshanks Fund and Scholarship Shepherd, clock-maker Ship-timbers, Machinery for sawing, Shirreff, Capt. Simmons Simms, F.W. Simms (see Troughton and Simms) Skeleton forms Sly, draughtsman Smith, Rev. R. Smith, father-in-law of G.B.A., and Mrs Smith, Smith, the Misses Smith, sisters of Richarda Airy, Susanna; Elizabeth; Georgiana; Florence; Caroline Smith, Archibald Smith, M., pupil Smith's Prizes Smyth, Capt. W.H. Smyth, Piazzi Societies, &c., Elections to (see Elections) Solar Eclipses (see Eclipses) Solar Inequality (see Sun) Solar System (see Sun) Solar Tables (see Sun) South, Sir James South's Telescope South-Eastern Railway Southampton Southey (Poet) Spectroscopy Spottiswoode Spring-Rice, Lord Monteagle Standards of Length and Weight, and Standards Commission Stars Start Point Steam-engines Stephenson, George Stephenson, Robert Steventon Stewart, Prof. Balfour Stjerneld, Baron Stokes, Prof. Stone, Astronomer Stratford, Lieut. Stroganoff, Count Strutt, Lord Belper Strutt, Jedediah Struve, Otto Stuart, Prof. J. Sun: Miscellaneous Parallax of (see also Transits of Venus) Eclipses of (see Eclipses) Inequality, Venus and Earth Tables of Surveys (see Trigonometrical Surveys) Sussex, Duke of, Sutcliffe Sutcliffe, Miss Sydney University Sylvester Sweden, King of Tate Taylor, architect Taylor, First Assistant to Pond, Taylor, H. Telegraphs (see Galvanic communications) Telescopes (see also Cambridge Observatory Instruments, and Greenwich Observatory Instruments) Teneriffe Experiment Thames, the River, Theology (see also Hebrew Scriptures and Colenso) Thermometers Thermo-multiplier Thirlwall, Bishop Thomas, assistant Thompson, Master Trin. Coll. Thomson, Sir W. Tidal Harbour Commission Tides, Time-signals and Time (see also Galvanic communication, &c.) Time balls (see Time signals) Tinkler, pupil Tottenham, pupil Traill, Dr Transit Circle, Transits of Venus Trigonometrical Survey Trinity College, Cambridge Trinity House Tripos Examination (see Senate-House Examination) Troughton and Simms Tulley, optician Tupman, Capt Turner, pupil Turton, Prof. Tutorship Ulrich, J.G. Universities (see Cambridge, Dublin, Edinburgh, London, Melbourne, Oxford, Sydney) University Education (see also Smith's Prizes and Senate-House Examination) University Press, Uranus (see Neptune) Valencia (see also Longitude Determinations) Venus (see Planets, and Transits of Venus) Venus and Earth inequality (see Inequality) Vernon Harcourt (see Harcourt) Vetch, Capt. Vibrations of ground Vignoles, C.B., engineer Vulliamy, clockmaker Wales, Prince of Walker, Byatt Walker, James, engineer Walker, Sydney, Warburton, H. Washington, Capt. Water telescope (see also Fluid telescope) Watson Waves (see Tides) Webster, M.P. for Aberdeen Western Westminster clock (see also Clocks) Wexford harbour (see Harbours) Wheatstone Whewell, William White House, the, Wigram, pupil Williams, John Williamson, pupil Williamstown Observatory Wilson, Prof. Winchester Winds (see Meteorology) Winning Wood, Sir Charles Wood, Dr Woodbridge, Suffolk Woodhouse, Prof. Woolwich Academy (see Examinations) Wordsworth, Dr, Master of Trin. Coll. Wordsworth, poet Wrede, Baron Wynter, Vice-Chancellor, Oxford Yolland, Col. York Cathedral Young, Dr