Part 97

We now come to that great discovery, which lay concealed from the most subtle and penetrating geniuses amongst mankind, until these latter ages; which so prodigiously enlarged the fields of astronomy, and with such rapidity handed down one curiosity after another, from the heavens to astonished mortals, that no one capable of raising his eyes and thoughts from the ground he trod on, could forbear turning his attention, in some degree, to the subject that engages us this evening.

Galileo, as he himself acknowledges, was not the first inventor of the telescope, but he was the first that knew how to make a proper use of it. If we consider that convex and concave lenses had been in use for some centuries, we shall think it probable that several persons might have chanced to combine them together, so as to magnify distant objects; but that the small advantage apparently resulting from such a discovery, either on account of the badness of the glasses or the unskilfulness of the person in whose hands they were, occasioned it to be neglected.

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Footnote A20:

The true invention of the telescope cannot be carried back to an earlier date than the beginning of the seventeenth century. Johannes Baptista Porta, a Neapolitan, in his Natural Magic, which was published in the year 1589, says, “Si utramque (lentem concavam et convexam) recté componere noveris, et longinqua et proxima majora et clara videbis:” and he is said to have made a telescope, accordingly, about the year 1594. But Porta is represented as having made this discovery such as it was, by accident; and, as not well understanding the proper use of his own invention.

According to Baron Bielfeld, however, telescopes were first constructed a long time after, in Holland; some say, by John Lippersheim, a spectacle-maker at Middelbourg in Zealand; others, by James Metius, brother to the celebrated professor Adrian Metius, of Franeker. Although the invention of this instrument, of indispensable use in astronomy, is sometimes attributed to the great Galileo, he has himself acknowledged, in his treatise, entitled Nuncius Siderius, that he took the hint from a report of a German having invented an instrument, by means of which, and with the assistance of certain glasses, distant objects might be distinguished as clearly as those that were near. This is precisely what Porta had mentioned in his book, in 1589; and therefore, if Galileo had not referred to a German, he might be supposed to have had in his view the Neapolitan’s conception of a telescope, announced long before such an instrument was properly constructed.

Whatever may have been the merit of Porta’s discovery, or the pretensions of Lippersheim, the spectacle-maker, and Metius, Peter Borel (in his treatise De vero Telescopii Inventore) is of the opinion that Zachariah Johnson, who, like Lippersheim, was a spectacle-maker, and in the same city, made this discovery by chance, about the year 1500; that Lippersheim imitated him, after making numerous experiments; and that he instructed Metius. There are others, who have been considered as having had some sort of claim to this important invention; among whom were a Mr. Digges, of England, and a M. Hardy, of France, both towards the commencement of the seventeenth century.

It is certain, however, that Galileo in Italy, (who died in 1642, aged seventy-eight years,) and, according to Bielfeld, Simon Marius in Germany, were the first that applied the telescope to the contemplation of celestial objects. W. B.

Footnote A20a:

Elem. of Univ. Erud. b. i. ch. 49.

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But Galileo, by great care in perfecting his telescope, and by applying a judicious eye, happily succeeded; and with a telescope magnifying but thirty times, discovered the moon to be a solid globe, diversified with prodigious mountains and vallies, like our earth; but without seas or atmosphere. The sun’s bright disk, he found frequently shaded with spots, and by their apparent motions proved it to be the surface of a globe, revolving on its axis in about five and twenty days. This it seems was a mortifying discovery to the followers of Aristotle; who held the sun to be perfect without spot or blemish. Some of them, it is said, insisted that it was but an illusion of the telescope and absolutely refused to look through one, lest the testimony of their senses should prove too powerful for their prejudices.

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Footnote A21:

In treating of the astronomy of the Greeks, Lalande contents himself with barely introducing the name of Aristotle, among their philosophers; seeming to consider him as one who had done very little for astronomical science. This philosopher (who died in the sixty-third year of his age, and only 322 years B. C.) among his other doctrines, not only maintained the eternity of the world; but, that Providence did not extend itself to sublunary beings: and as to the immortality of the soul, it is uncertain whether he believed it or not. Bayle calls his logic and his natural philosophy, “the weakest of his works:” and says, further; “It will be an everlasting subject of wonder to persons who know what philosophy is, to find that Aristotle’s authority was so much respected in the schools, for several ages, that, when a disputant quoted a passage from this philosopher, he who maintained the thesis durst not say, Transeat; but must either deny the passage or explain it in his own way.” W. B.

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Galileo likewise discovered the four attendants of Jupiter, commonly called his satellites: Which at first did not much please that great ornament of his age, the sagacious Kepler. For by this addition to the number of the planets, he found their Creator had not paid that veneration to certain mystical numbers and proportions, which he had imagined. Let us not blush at this remarkable instance of philosophical weakness, but admire the candour of the man who confessed it.

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Footnote A22:

This discovery was made on the 8th of January, 1610. It was, as Mr. Vince observes, a very important one in its consequences; as it furnished a ready method of finding the longitude of places, by means of their eclipses. W. B.

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Galileo not only discovered these moons of Jupiter, but suggested their use in determining the longitude of places on the earth; which has since been so happily put in practice, that Fontenelle does not hesitate to affirm, that they are of more use to Geography and Navigation, than our own moon. He discovered the phases of Mars and Venus; that the former appears sometimes round and sometimes gibbous, and that the latter puts on the shapes of our moon: And from this discovery, he proved to a demonstration, the truth of the Copernican System. Nor did that wonderful ring, which surrounds Saturn’s body, without touching it, and which we know nothing in nature similar to, escape his notice; though his telescope did not magnify sufficiently to give him a true idea of its figure.

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Footnote A23:

Although both Geography and Navigation have been wonderfully improved by the important discoveries made by the moderns in astronomy, they have nevertheless, derived the most essential aid from the application of the Compass to their purposes.

The invention of this instrument, which is of indispensible utility, is almost universally ascribed to Flavio Gioia, a native of Amalfi in the kingdom of Naples. He is called, by some writers, Flavio de Melfi, (by which is meant, Flavio of Amalfi, this town being the place of his nativity;) and his invention of the Compass is placed in the year 1302. But it is affirmed by others, that Paulus Venetus brought the Compass first into Italy from China, in the year 1260. The Chinese Compass, however, whatever may be its antiquity, appears to have been a very imperfect instrument, compared with the modern Mariner’s Compass; and, more especially, with the Azimuth Compass, as improved by Dr. Knight and Mr. Smeaton. The Chinese Compass, now used, is represented as being nothing more than a magnetic needle kept floating, by means of a piece of cork, on the surface of water, in a white china ware vessel, divided at bottom into twenty-four points.

It is worthy of observation, that the French have laid claim to the invention of the Compass, upon no better foundation than the circumstance of a fleur de lys being always placed at the north point of the chard; although it is known, that Gioia decorated the north end of the needle with that flower in compliment to his own sovereign, who bore it in his arms, as being descended from the royal house of France. “It hath been often,” says Dr. Robertson, “the fate of those illustrious benefactors of mankind, who have enriched science and improved the arts by their inventions, to derive more reputation than benefit from the happy efforts of their genius. But,” continues this eminent historian, “the lot of Gioia has been still more cruel; through the inattention or ignorance of contemporary historians, he has been defrauded even of the fame to which he had such a just title. We receive from them no information with respect to his profession, his character, the precise time when he made this important discovery, and the accidents and enquiries which led to it: the knowledge of this event, though productive of greater effects than any recorded in the annals of the human race, is transmitted to us without any of those circumstances which can gratify the curiosity that it naturally awakens.” W. B.

Footnote A23a: