We add a few notes on Bird naturalists. The Redbreast has been called the Naturalist's Barometer. When on a summer evening, though it be unsettled and rainy, he sings cheerfully and sweetly on a lofty twig or housetop, it is an unerring promise of succeeding fine days. Sometimes, though the atmosphere be dry and warm, he may be seen melancholy chirping and brooding in a bush or low in a hedge; this promises the reverse. In the luxuriant forests of Brazil the Toucan may be heard rattling with his large hollow beak, as he sits on the outermost branches, calling in plaintive notes for rain.
When Mr. Loudon was at Schwetzingen, Rhenish Bavaria, in 1829, he witnessed in the post-house there for the first time what he afterwards frequently saw—an amusing application of zoological knowledge for the purpose of prognosticating the weather. Two tree-frogs were kept in a crystal jar about eighteen inches high and six inches in diameter, with a depth of three or four inches of water at the bottom, and a small ladder reaching to the top of the jar. On the approach of dry weather the frogs mounted the ladder, but when moisture was expected they descended into the water. These animals are of a bright green, and in their wild state climb the trees in search of insects, and make a peculiar singing noise before rain. In the jar they got no other food than now and then a fly; one of which, Mr. Loudon was assured, would serve a frog for a week, though it would eat from six to twelve flies in a day if it could get them. In catching the flies put alive into the jar the frogs displayed great adroitness.
Snails are extraordinary indicators of changes in the weather. Several years ago, Mr. Thomas, of Cincinnati, known as an accredited observer of natural phenomena, published some interesting accounts of Weather-wise Snails. They do not drink (he observes), but imbibe moisture in their bodies during rain, and exude it at regular periods afterwards. Then a certain snail first exudes the pure liquid; when this is exhausted, a light red succeeds, then a deep red, next yellow, and lastly a dark brown. The snail is very careful not to exude more of its moisture than is necessary. It is never seen abroad except before rain, when we find it ascending the bark of trees and getting on the leaves. The tree-snail is also seen ascending the stems of plants two days before rain: if it be a long and hard rain they get on the sheltered side of the leaf, but if a short rain the outside of the leaf. Another snail has the same habits, but differs only in colour: before rain it is yellow, and after it blue. Others show signs of rain, not only by means of exuding fluids, but by means of pores and protuberances; and the bodies of some snails have large tubercles rising from them before rain. These tubercles commence showing themselves ten days previous to the fall of rain they indicate; at the end of each of these tubercles is a pore; and at the time of the fall of rain these tubercles, with their pores opened, are stretched to their utmost to receive the water. In another kind of snail, a few days before rain appears a large and deep indentation, beginning at the head between the horns, and ending with the jointure at the shells. Other snails, a few days before the rain, crawl to the most exposed hill-side, where, if they arrive before the rain descends, they seek some crevice in the rocks, and then close the aperture of the shell with glutinous substance; this, when the rain approaches, they dissolve, and are then seen crawling about.
Our Cincinnati observer mentions three kinds of snails which move along at the rate of a mile in forty-four hours; they inhabit the most dense forests, and it is regarded as a sure indication of rain to observe them moving towards an exposed situation. Others indicate the weather not only by exuding fluids, but by the colour of the animal. After rain the snail has a very dark appearance, but it grows of a bright colour as the water is expended; whilst just before rain it is of yellowish white colour, also just before rain streaks appear from the point of the head to the jointure of the shell. These snails move at the rate of a mile in fourteen days and sixteen hours. If they are observed ascending a cliff it is a sure indication of rain: they live in the cavities of the sides of cliffs. There is also a snail which is brown, tinged with blue on the edges before rain, but black after rain: a few days before appears an indentation, which grows deeper as the rain approaches.
The leaves of trees are even good barometers: most of them for a short, light rain, will turn up so as to receive their fill of water; but for a long rain they are doubled, so as to conduct the water away. The Frog and Toad are sure indicators of rain; for, as they do not drink water but absorb it into their bodies, they are sure to be found out at the time they expect rain. The Locust and Grasshopper are also good indicators of a storm; a few hours before rain they are to be found under the leaves of trees and in the hollow trunks.
The Mole has long been recorded as a prognosticator of change of weather, before which it becomes very active. The temperature or dryness of the air governs its motions as to the depth at which it lives or works. This is partly from its inability to bear cold or thirst, but chiefly from its being necessitated to follow its natural food, the earth-worm, which always descends as the cold or drought increases. In frosty weather both worms and moles are deeper in the ground than at other times; and both seem to be sensible of an approaching change to warmer weather before there are any perceptible signs of it in the atmosphere. When it is observed, therefore, that Moles are casting hills through openings in the frozen turf or through a thin covering of snow, a change to open weather may be shortly expected. The cause of this appears to be—the natural heat of the earth being for a time pent in by the frozen surface accumulates below it; first incites to action the animals, thaws the frozen surface, and at length escapes into the air, which is warm, and softens; and if not counterbalanced by a greater degree of cold in the atmosphere brings about a change, such as from frosty to mild weather. The Mole is most active and casts up most earth immediately before rain, and in the winter before a thaw, because at those times the worms and insects begin to be in motion, and approach the surface.
Forster, the indefatigable meteorologist, has assembled some curious observations on certain animals, who, by some peculiar sensibility to electrical or other atmospheric influence, often indicate changes of the weather by their peculiar motions and habits. Thus:—
Ants.—An universal bustle and activity observed in ant-hills may be generally regarded as a sign of rain: the Ants frequently appear all in motion together, and carry their eggs about from place to place. This is remarked by Virgil, Pliny, and others.
Asses.—When donkeys bray more than ordinarily, especially should they shake their ears, as if uneasy, it is said to predict rain, and particularly showers. Forster noticed that in showery weather a donkey brayed before every shower, and generally some minutes before the rain fell, as if some electrical influence, produced by the concentrating power of the approaching rain-cloud, caused a tickling in the wind-pipe of the animal just before the shower came on. Whatever this electric state of the air preceding a shower may be, it seems to be the same that causes in other animals some peculiar sensations, which makes the peacock squall, the pintado call "come back," &c. An expressive adage says:—
"When that the ass begins to bray,