Part 9

In one of the East London suburbs, near to the reservoirs of a water company, it has been found worth while to create an artificial spring, by making an arrangement with the waterworks for a constant supply. This flows from a stand-pipe and irrigates the cress-beds, which produce good cresses, though not of such fine flavour as those grown in natural spring water and upon a chalk soil.

Fishermen in the Isle of Wight send all the way to the Midlands to get the little scarlet withes required for making lobster-pots.

FOG AND DEW PONDS

The cycle of dry seasons seems to be indefinitely prolonged. During the period, now lasting since 1893, in which we have had practically no wet summers, and many very hot ones, a very curious phenomenon has been remarked upon the high and dry chalk downs. The dew ponds, so called because they are believed to be fed by dew and vapours, and not by rain, have kept their water, while the deeper ponds in the valleys have often failed. The shepherds on the downs are careful observers of these ponds, because if they run dry they have to take their sheep to a distance or draw water for them from very deep wells. They maintain that there are on the downs some dew ponds which have never been known to run dry. Others which do run dry do so because the bottom is injured by driving sheep into them and so perforating the bed when the water is shallow, and not from the failure of the invisible means of supply. There seem to be two sources whence these ponds draw water, the dew and the fogs. Summer fogs are very common at night on the high downs, though people who go to bed and get up at normal hours do not know of them. These fogs are so wet that a man riding up on to the hills at 4 a.m. may find his clothes wringing wet, and every tree dripping water, just as during the first week of last November in London many trees distilled pools of water from the fog, as if it had been pouring with rain. Such was the case on July 4th, 1901. The fogs will draw up the hollows towards the ponds, and hang densely round them. Fog and dew may or may not come together; but generally there is a heavy dew deposit on the grass when a fog lies on the hills. After such fogs, though rain may not have fallen for a month, and there is no water channel or spring near the dew pond, the water in it rises prodigiously. Every shepherd knows this, but the actual measurements of this contribution of the vapour-laden air have not often been taken. Yet the subject is an interesting one, and of real importance to all dwellers on high hills, especially those which, like the South Downs, are near the sea, and attract great masses of fog and vapour-laden cloud, but contain few springs on the high rolls of the hills.

The following are some notes of the rise in a dew pond caused by winter fogs on the Berkshire Downs. They were recorded by the Rev. J.G. Cornish at Lockinge, in Berkshire, and taken at his suggestion by a shepherd in a simple and ingenious way. Whenever he thought that a heavy dew or fog was to be expected (and the shepherds are rarely wrong as weather prophets) he notched a stick, and drove it into the pond overnight, so that the notch was level with the surface. Next morning he pulled it up, marked how high the water had risen above the notch, and nicked it again for measurement. On January 18th, after a night of fog, the water rose 1-1/2 in.; on the next day, after another fog, 2 in.; and on January 24th, 1 in. Five nights of winter fog gave a total rise of 8 ins.--a vast weight of water even in a pond of moderate area. Five days of heavy spring dew in April and May, with no fog, gave a total rise in the same pond of 3-1/2 ins., the dews, though one was very heavy, giving less water than the fogs, one of which even in May caused the water to rise 1-1/2 ins. The shepherds say that it is always well to have one or two trees hanging over the pond, for that these distil the water from the fog. This is certainly the case. The drops may be heard raining on to the surface in heavy mists. During the first October mists of 1891 the pavement under certain trees was as wet as if it had been raining, while elsewhere the dust lay like powder. The water was still dripping from these trees at 7 a.m. Under the plane-trees the fallen leaves were as wet from distilled moisture as if they had been dipped in water; yet the ground beyond the spread of the tree was dry. The writer tried a simple experiment in this distilling power of trees. At sundown, two vessels were placed, one under a small cherry-tree in full leaf, the other on some stone flags. Heavy dew was falling and condensing on all vegetation, and on some other objects, with the curious capriciousness which the dewfall seems to show. The leaves of some trees were already wet. In the morning the vessel under the tree, and that in the open, both held a considerable quantity of water, that on the stone caught from dew and condensation, that under the tree mainly from what had dripped from the leaves, which clearly intercepted the direct fall of dew. But the vessel under the tree held just twice as much water as that in the open, the surplus being almost entirely derived from drops precipitated from the leaves. Mr. Sanderson, the manager of the elephant-catching establishment of the Indian Government, noted that in heavy dews in the jungle the water condensed by the leaves could be heard falling like a heavy shower of rain.

Gilbert White, who noticed everything, and lived near a chalk hill, makes some shrewd conjectures, both about the dew ponds and the part which trees play in distilling water from fog, though he does not form the practical conclusion, which we think is a safe one, that the most fog-distilling trees should be discovered and planted to help to supply the water in these air-tapping reservoirs. "To a thinking mind," he writes, "few phenomena are more strange than the state of little ponds on the summits of the chalk hills, many of which are never dry in the most trying droughts of summer. On chalk hills, I say, because in many rocky and gravelly soils springs usually break out pretty high on the sides of elevated grounds and mountains; but no persons acquainted with chalky districts will allow that they ever saw springs in such a soil but in valleys and bottoms, since the waters of so pervious a stratum as chalk all lie on one dead level, as well-diggers have assured me again and again. Now we have many such little round ponds in this district, and one in particular on our sheep-down, three hundred feet above my house, and containing perhaps not more than two or three hundred hogsheads of water; yet it is never known to fail, though it affords drink for three or four hundred sheep, and for at least twenty head of large cattle beside. This pond, it is true, is overhung with two moderate beeches, that doubtless at times afford it much supply. But then we have others as small, which, without the aid of trees, and in spite of evaporation from sun and wind and perpetual consumption by cattle, yet constantly contain a moderate share of water, without overflowing in the winter, as they would do if supplied by springs. By my Journal of May, 1775, it appears that 'the small and even the considerable ponds in the vales are now dried up, but the small ponds on the very tops of the hills are but little affected.' Can this difference be accounted for by evaporation alone, which is certainly more prevalent in the bottoms? Or, rather, have not these elevated pools some unnoticed recruits, which in the night time counterbalance the waste of the day?" These unnoticed recruits, though it is now certain that they come in the form of those swimming vapours from which little moisture seems to fall, are enlisted by means still not certainly known. The common explanation was that the cool surface of the water condensed the dew, just as the surface of a glass of iced water condenses moisture. The ponds are always made artificially in the first instance, and puddled with clay and chalk.

In the notes to a recent edition of "White's Selborne," edited by Professor L.C. Miall, F.R.S., and Mr. W. Warde Fowler, a considerable amount of information on dew ponds is appended to the passage quoted above, but the source of supply still remains obscure. The best dew ponds seem to be on the Sussex Downs, where far more fog and cooling cloud accumulates than on the more inland chalk ranges, because of the nearness of the sea. Near Inkpen Beacon, in Hampshire, there is a dew pond at a height of nine hundred feet, which is never dry, though it waters a large flock of sheep. Dew ponds are often found where there are no other sources of supply, such as the wash coming from a road. Probably if the site for one had to be selected, it should be where the mists gather most thickly and the heaviest dews are shed, local knowledge only possessed by a few shepherds. I have driven up through rain on to the top of the downs, and found there that no rain was falling, but mists lying in the hollows like smoke. Mr. Clement Reid, F.R.S., has added to the "Selborne" notes his own experiences of the best sites for dew ponds. They should, he thinks, be sheltered on the south-west by an overhanging tree. In those he is acquainted with the tree is often only a stunted, ivy-covered thorn or oak, or a bush of holly, or else the southern bank is high enough to give shadow. "When one of these ponds is examined in the middle of a hot summer's day," he adds, "it would appear that the few inches of water in it could only last a week. But in early morning, or towards evening, or whenever a sea-mist drifts in, there is a continuous drip from the smooth leaves of the overhanging tree. There appears also to be a considerable amount of condensation on the surface of the water itself, though the roads may be quite dry and dusty. In fact, whenever there is dew on the grass the pond is receiving moisture."

Though this is evidently the case, no one has explained how it comes about that the pond surface receives so very much more moisture than the grass. The heaviest dew or fog would not deposit an inch, or even two inches, of water over an area of grass equal to that of the pond. None of the current theories of dew deposits quite explain this very interesting question. Two lines of inquiry seem to be suggested, which might be pursued side by side. These are the quantities distilled or condensed on the ponds, and the means by which it is done; and secondly, the kind of tree which, in Gilbert White's phrase, forms the best "alembic" for distilling water from fog at all times of the year. It seems certain that the tree is an important piece of machinery in aid of such ponds, though many remain well supplied without one.

Thomas Elliot, who for some twenty years was shepherd and general manager for one of my father's tenants at Childrey.

Full details of the cost and method of making dew ponds, as well as other information about them, are contained in the prize essay of the late Rev. J. Clutterbuck, Rector of Long Wittenham, in the Journal of the Royal Agricultural Society. Vol. I., Sec.S. Part 2.

In the Isle of Wight, on Brightstone Downs, about 400 feet above the sea, is a dew pond with a concrete bottom, which has never run dry for thirty years.

POISONOUS PLANTS

A friend informs me that he has found a quantity of woad growing on the Chilterns above the Thame, enough to stain blue a whole tribe of ancient Britons, and also that on a wall by the roadside between Reading and Pangbourne he discovered several plants of the deadly nightshade, or "dwale." This word is said to be derived from Old French deuil, mourning; but its present form looks very English. The only cases of plant poisoning now common among grown-up people are those caused by mistaking fungi for mushrooms, or by making rash experiments in cooking the former, of which Gerard quaintly says: "Beware of licking honey among the thorns, lest the sweetness of the one do not countervail the sharpness and pricking of the other." But with such a list of toxic plants as our flora can show there is always danger from certain species whose properties are quite unknown to ordinary mortals. Are they equally unknown to the herbalists and that mysterious trade-union of country-women and collectors of herbs by the roadside who deal with them? Probably the trade in poisons not used for serious purposes, but for what used in some parts of England to be called "giving a dose," a punishment for unfaithful, unkind, or drunken husbands, still exists as it did some forty years ago. The collectors of medicinal plants cut from the roadside and rubbish heaps, plants whose "operations" for good are quite well known, and have been handed down by tradition for centuries, cannot be absolutely ignorant of the other side of the picture, the toxic properties which other plants, or sometimes even the same plants, contain. Foxglove, for instance, from which digitalis used as a medicine is extracted, is a good example of these kill-or-cure plants. Every portion of the plant is poisonous, leaves, flowers, stalks, and berries. It affects the heart, and though useful in cases in which the pulsations are abnormal, its symptoms when taken by persons in ordinary health are those of heart failure. Thus foxglove is not only a dangerous but a "subtle" poison.

Among other plants which may cause serious mischief, but are seldom suspected, are such harmless-looking flowers as the meadowsweet, herb-paris, the common fool's-parsley, found growing in quantities in the gardens of unlet houses and neglected ground which has been in cultivation, mezereon, columbine, and laburnum. Meadowsweet has the following set against its name: "A few years since two young men went from London to one of the Southern counties on a holiday excursion, on the last day of which they gathered two very large sheafs of meadowsweet to bring home with them. These they placed in their bedroom at the village inn where they had to put up. In the course of the night they were taken violently ill, and the doctor who was called in stated that they were suffering from the poisonous prussic-acid fumes of the meadowsweet flowers, which he said almost overpowered him when he came into the room. The flowers were at once removed, and the young men, treated with suitable restoratives, were by next morning sufficiently recovered to undertake the journey home." Without knowing what the young men had had for supper, it seems perhaps rather hasty to blame the meadowsweet. But the other flowers mentioned above have a bad record. To take them in order. Herb-paris, which grows in woods and shady places, with four even-sized leaves in a star at the top of the stem, all growing out opposite each other, bears a large, green solitary flower, and a bluish-black berry later. All parts of the plant are poisonous, the berries especially. Fool's-parsley, an unpleasantly smelling, very common plant, which leaves its odour on the hand if the seeds are squeezed or drawn through it, is said to cause numbers of deaths by being mistaken for common parsley and cooked. In the case of poisoning by this plant, it is recommended that milk should be given, the body sponged with vinegar, and mustard poultices put on the sufferer's legs. It is reckoned that one plant produced six thousand and eighty seeds--an unpleasant degree of fecundity for a poisonous weed. Columbine, which is a wild plant with blue or white flowers, as well as a domesticated one, has a toxic principle like that of the monkshood, more especially in the seeds; and the pretty red berries of the mezereon are responsible for the deaths or illness of children nearly every autumn. They are like cherries, and easily picked from the low bushes on which they grow. A dozen are said to be enough to cause death, though this must probably depend on the state of the eater's health. The laburnum, with its golden rain, is potentially a kind of upas tree. The writer has only known of two deaths of children caused by eating the beans in the green pods, but it is said to be a frequent cause of death every year on the Continent, where, possibly, children are less naturally careful about poisonous plants than those in England, to whom risks of this kind are usually and properly made part of the "black list" of the nursery-book of "Don'ts." The seeds will even poison poultry, if they pick them up after they have dropped from the pod. Laburnum is of comparatively recent introduction into Britain, or it would probably earlier have been accorded a place among the severely poisonous plants, dreaded by all.

Of these the deadly nightshade and hemlock are the best known in story, while the yew is most dangerous because far more common. In one case the Rector of a Berkshire village was made very ill by eating honey which had been partly gathered from yew flowers. Green hellebore and monkshood are also classed in the list of the ranker poisons. Deadly nightshade is rather a rare plant, yet it may be seen often enough on the sides of woods where there are old walls. It is poisonous throughout. The flowers are large, single, purple bells, and the berries black and shiny like a black cherry. It is said of this dangerous plant that the roots are computed to be five times more poisonous than the berries, that human beings have been found more susceptible to it than animals, and carnivorous animals more so than others. Children suffer more in proportion to the quantity of poison taken than do adults. But cases of nightshade poisoning are very rare, though two were reported some three years ago. Possibly the berries often fail to ripen, and so are less attractive in appearance. The poisonous hemlocks are two, one of which, the common hemlock, is said to have been the plant from which the Athenians prepared their poison for executing citizens condemned to death; and the other, the water-hemlock, or cowbane, is particularly deadly when eaten by cattle, to which it is fatal in a very few hours. Another plant, used for preparing poison in India, which produces a drug used by some tribes of Thugs for procuring the death of their victims, datura or stramonium, has now found a place amongst our wild flowers. It has an English name, thorn-apple, and is said to have been naturalised by the gipsies, who used the seeds as a medicine and narcotic, and carried them about with them in their wanderings. Like henbane, it is often seen on rubbish-heaps and in old brickfields. The leaf is very handsome, and the flower white and trumpet-shaped. Both this plant and the henbane retain their poisonous properties even when dried in hay, and stalled cows have been known to be poisoned by fodder containing a mixture of the latter plant.

Cattle have a delicate sense of smell which warns them of the danger of most poisonous English herbs, though apparently this warning odour is absent from the plants which kill so many horses when the grass grows on the South African veld, and also from our English yew. Yew was anciently employed as a poison in Europe, much as is the curari to-day in Central America. Dr. W.T. Fernie, the author of "Herbal Simples Approved for Modern Use," says that its juice is a rapidly fatal poison, that it was used for poisoning arrows, and that the symptoms correspond in a very remarkable way with those which follow the bites of venomous snakes. It is believed that in India there is a poison which produces the same effect. An Indian Rajah once desired that a notice should be put in a well-known paper that he did not intend to raise his rents on his accession to the estates. The proprietor of the paper asked him his reasons for wishing for such an advertisement. The Rajah said that his grandfather had raised the rents, and had died of snake-bite; that his father had done the same, and had also died of snake-bite; and that he concluded that there was some connection of cause and effect. The notice was inserted, and this Rajah did not die of snake-bite, or rather of the poison which simulates it.

"Farm and Home" Year Book for 1902.

ANCIENT THAMES MILLS

Almost the greatest loss to country scenery is the decay of the ancient windmills and water-mills. The first has robbed the hilltops of a most picturesque feature, while in the valleys and little glens the roaring, creaking, dripping wheel sounds no longer, except in favoured spots where it still pays to grind the corn in the old way. The old town and city mills often survived longer than the country ones, and those on the Thames longer than those on smaller rivers. The corn and barley which was taken to market in the town was easily transferred to the town mill, and thence by water to the place of consumption. Every Wykehamist remembers the ancient and picturesque mills of Winchester, with the mill-stream bridged by the main street. At Oxford some of the most ancient mills remain to this day, while others have only recently been destroyed, or have undergone a curious conversion into dwelling-houses, beneath which the mill-stream still rushes. One of these houses stands near Folly Bridge; another old mill has just undergone the same process, that close to Holywell Church. Some of these mills are the most ancient surviving institutions in Oxford, far older than the colleges--older even than any of the churches except perhaps one. Some of these--the Castle Mill, for instance--have ground corn for centuries since the abbeys, for whose use they were founded, utterly disappeared. Others were standing long before abbeys or colleges were founded, and were part of their endowments. They are the oldest link between town life and country life left in Oxford, or indeed in England. For a thousand years the corn grown on the hills beyond the Thames meadows has been drawn to their doors. Saxon churls dragged wheat there on sledges, Danes rowed up the river to Oseney and stole the flour when they sacked the abbey, Norman bishops stole the mills themselves. That iniquitous Roger of Salisbury was "in" this, as we might guess. Roger, who knew that attention to detail is the soul of business, commandeered this particular mill with others in these parts, and, when forced to let it go, with a fine sense of humour made it over to the Godstone nunnery as a pious donor.

The Knights Templars had another mill at Cowley, and the king himself one on the Cherwell, which was given to the Hospital of St. John, who "swapped" it with Merton. Later on these mills helped King Charles's army vastly, for all the flour needed for the Oxford garrison was ground inside or close to the walls.

At present the Thames is mainly visited as a source of rest and refreshment to tens of thousands of men "in cities pent," and of pleasure rather than profit. In a secondary degree it is useful as a commercial highway, the barge traffic being really useful to the people on its banks, where coal, stone for road-mending, wood, flour, and other heavy and necessary goods are delivered on the staithes almost at their doors. But when the old mills were first founded, and for eight centuries onwards, it was as a source of power, a substitute for steam, that the river was valued. The times will probably alter, and the Thames currents turn mill wheels again to generate electric light for the towns and villages on its banks. The chance of this coming about is enough to make any one who owns a mill right on the water keep it, even though not useful at present. First the old roads with auto-cars, then the old mills with hydraulic lighting and low-power dynamos will come to the front again. Whereof take the old story of the Oxford river as full and sufficient witness, and Antony Wood for storyteller. "Oxford," he says, "owed its prosperity to its rivers," of which there were apparently as many branches and streams then as now.

The rivers were "beneficial to the inhabitants, as anon shall be showed," though the Cherwell was "more like a tide" than a common river sometimes, and once nearly overflowed all the physic garden. That garden stands there still. So does the Cherwell still behave "more like a tide than a river," and the scene at the torpid races a few years ago is evidence that the rivers have not diminished in volume. What, then, was the "great commodity" given by them to the city? First and least, a water which was good for dyeing cloth and for tanning leather; secondly, and by far the greatest benefit, it turned the wheels of at least a dozen important mills. As mills were always a monopoly, as much opposition was raised to the making of a new one as would now be evoked by the proposal to construct a new railway.

It was meddling with vested interests of a powerful kind, but there were so many rivers at Oxford that each turned one or two mills without injuring any one's water rights.

Of all these mills, the greatest advantage to the city came from the Castle Mill. Notwithstanding its name, this was not the property of the Castle of Oxford, though it stood within arrow-shot of its towers, and was thus protected from pillage in time of war. It stands under the remaining tower, the water tower, of the castle still, and on exactly the same site, and on the branch of the Thames which from the most ancient days has been the waterway by which barges and merchandise came from the country to the city, bringing goods from Abingdon or corn and fuel from the upper river. And it is still called by its old name of the Weir Stream. "There is one river called Weyre, where hath bin an Hythe, at which place boatmen unload their vessels, which also maketh that antient mill under the castle seldom or never to faile from going, to the great convenience of the inhabitants." So says Antony Wood, adding that it stood before the Norman conquest. After that it was forfeited to the Norman kings, and then held in half shares by the burgesses of the town and the abbots of Oseney, that once wealthy and now vanished abbey, which stood close by where the railway station now is. They shared the fishery also, and apparently this partnership prevented friction between the town and the monks, as each could undersell the other, and prices for flour and fish were kept down at a reasonable figure.

Henry VIII. gave the abbey's share to the new bishopric of Oxford, but the funds of the bishopric were embezzled by some means, and the town ultimately bought the mill for L566.

St. George's Tower, the only remaining fragment of the castle, is built of stones and mortar, so compact that though the walls have stood since Robert d'Oily reared it, late in the reign of the Conqueror, the stones and mortar had to be cut out as if from a mass of rock when a water-pipe was recently taken through the walls. It is now the water tower which holds the supply for Oxford prison.

Old Holywell Mill was on a branch of the Cherwell, and stood just behind Magdalen Walks, whence a charming view was had of its wheel and lasher. It belonged to the Abbey of Oseney, who gave it to Merton College in exchange for value. Now it is a handsome dwelling-house, below which the mill stream rushes.

Merton College seems to have had a fancy for owning mills, for it also acquired by exchange the King's Mill. Only the house and lasher are left to show where this old mill stood. It had a narrow but very strong mill stream, which in winter used to come down in a sheet of solid water like green jade, a beautiful object among the walks and willows of Mesopotamia. It was an outpost of the King's forces when Oxford was held for the Royalists.