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necessity for supposing with Aristotle and M. De Luc that the gases, to form the Meteors, should ascend from the earth, nor any proof of their ascent; but it may be by means of gases somewhere formed aloft and taking fire that the meteoric stones are formed. The The way, in which electricity may be concerned in these processes is at present unknown: and the accounts of the fall of these stones, and the various hypotheses about their causes, are too numerous to admit of a detail of them here. I merely wish to call the attention of Meteorologists to the apparent similiarity of principle of those flaming Meteors which are, and of those which are not, visibly attended with the fall of Aërolites.*
* For Analyses of Aërolites, see Thomson's System of Chemistry, Phil. Mag. &c. For further particulars see also the Chapter on Electricity.
One of the largest Meteoric Stones which has been found, is preserved in M. Sowerby's Museum, at Lambeth in Surry.
ONE of the principal purposes to which meteorology may be applied is, that of enabling
to predict, in some measure, the ensuing changes of the weather. In order to do this accurately, a familiar acquaintance with the modifications of the clouds, and indeed with all the operations which are going on above, appears to be necessary. I hardly need lay down the following rule for predicting atmospheric changes. That when two or more contrary inclinations appear, the result must be deduced from those which ultimately prevail; and that when several agreeable signs are seen together, the event may be considered as predicted with additional certainty.* Prognosticks
* A rule laid down of old and sung by Aratus, who says of Prognosticks,
Τῶν μδεν καλοκνησο, καλον δ' επι σηματι σημα
Arat. Dios. 412.
of weather may be divided into those which result from the observance of the sky, and of meteorological instruments; and those which are deducible from the habits and motions of particular animals and plants.
The popular prognosticks of Rain, Wind, and other changes of the weather, which with little variety are common in most countries, seem to have been known and observed with accuracy of old. Indeed their being familiar to almost every age and country affords the strongest confirmation of their correctness, to those who have not had constant experience of them.
Although we find familiar mention of the Signs of the Weather in the works of Homer, Hesiod, and among almost all the oriental writings, yet Theophrastus the Grecian naturalist, seems to have been the first who cultivated this branch of meteorological science, and collected together the proverbial rules of judging of the weather; which were shortly afterwards put into verse by Aratus the poet, in his Alonμela, above two thousand one hundred years ago, and are imitated by Virgil, Lucan, Pliny, Seneca, and others. With little variation, the same rules are to be found
scattered among numerous works of Natural History and Science. And they are popular among the lower classes of modern Europe. Such of them as I have collected by occasional conversation with Mariners, Shepherds, and other persons who spend their lives chiefly out of doors, and who are attentive in noticing these prognosticks, as well as those which I have noticed myself, have I collated with the written accounts of the ancient Greeks and Romans, and subjoined.
Of Prognosticks of Atmospheric Changes, deducible from the Motions of Animals.
It was long ago observed by the ancients that, from the peculiar motions and habits of many animals, the consequence, probably, of their sensations of pain or of pleasure, a very accurate judgment might be formed of the approaching changes of the weather; neither has this entirely escaped the notice of more modern meteorologists. But I think they have not bestowed that share of attention to
this subject which it certainly deserves. It is difficult, perhaps, to conceive the manner in which animals become sensible of the approach of particular kinds of weather. We cannot suppose that they are forewarned of it by the appearances of the sky, at least in many cases; for some animals express signs of uneasiness previous to an alteration of the weather, long before there are any visible signs of change, and often when they have no opportunity of observing what is going on abroad. Dogs, for instance, closely confined in a room, frequently become very drowsy and stupid before Rain. They often sleep all day before the fire, and are almost incapable of being roused.* The same, in a less degree, is observable in Cats. And a Leech, confined in a glass of water, has been found, by its rapid motions, or its quiescence, to indicate wet or fair weather. From an examination of the structure of the brain of animals, they do not appear organized to have any distinct notions of causation; but they can observe that two particular things are conjoined, or that they follow one another; and thus from
* On such occasions, I have sometimes found their ears considerably inflamed, a common symptom of illhealth in many animals.