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retain it, is violently shaken or rent in multitudes of places; andthis not only on the surface, hut to great depths. The electricitybeing now in some measure discharged from the earth, the oceanrushes forward with fury to discharge in its turn the excess of electricmatter it just before received from the earth. If there are volcanoesin the neighbourhood, the violent discharge of electricity manifestsitself by setting them in a llame ; and thus, till the equilibrium is re-stored all nature seems to be threatened with dissolution.—Even inthose places where the force of the electric fluid is not able to shakethe solid parts of the earth, it manifests its power by agitating thewaters in the maimer above described. Water being a much bet-ter conductor of electricity than earth, this subtile fluid, as soon asit can get out from the solid earth, flies to (he water. The con-sequence is, that the water immediately swells up, and is attractedby whatever part of the earth has less electricity than itself. Ilencethose strange irregular motions of the waters in different places,so particularly observed at the time of the earthquake at Lisbon ;and which it seems impossible to account for from any other causethan an immediate discharge of electric matter from the earth intothem. 9. As it is impossible that any part of the earth can be elec-trified, without communicating a proportionable share of electricityto the animals that live upon it, it thence follows, that there canbe no considerable commotion in the electric matter lodged in thebowels of the earth, without affecting that which is contained in thebodies of the animals. Ilence the brutes, who seem to be moresensible of such commotions than we, run about, and shew signs offear, before the earthquake comes on; and hence the giddiness,sickness, &c. which the human race are subject to, during the timeof the shock, even though they do not feel it, as was the case atGibraltar. 10. As the atmosphere hath a communication withthe earth, it is scarcely to be supposed that the earth can, for anylength of time, contain a considerable quantity of electric matter,without communicating to the atmosphere a proportionable quan-tity. Before an earthquake, therefore, we must suppose the elec-tricity of the earth and air to be in perfect equilibrio. Ilence theweather is serene, there is no wind, nor any other sign in the at-mosphere, of the terrible catastrophe that is about to ensue. Butthe moment the discharge is made from the earth, the equilibriumbetween terrestrial and atmospherical electricity is broken; theair either begins to receive the fluid from the earth, or the earthfrom the air. As there is not then time for the collection of thunderclouds by which the electricity may be brought down in suddenflashes of lightning, the fluid breaks through the substance of theair itself with dismal and horrid noises, which alw ays accompanyan earthquake. That this is the ease, seems highly probable froman experiment of M. deKomas, when, having brought down avast quantity of electric matter from the clouds by means of a kite,be heard the noise it made in the air, like the continual blowing ofa small forge bellows. In general, a considerable change ofweather takes place at the time of an earthquake, though not al-ways. In the earthquake which happened'in England in 1777,there was no remarkable change of weather there; biit, soon after,there was a great deal of thunder and lightning in the southernparts of Scotland : which secnis to indicate, that the electric fluiddischarged from the earth in England had taken its course north-ward, and produced the phenomena before mentioned in Scotland .The same observation may likewise be made with regard to 1789,when there were slight shocks of an earthquake both in Englandand Scotland . That in England was followed by an uncommonfrequency of thunder and lightning in the southern parts of Scot-land ; by the progress of the electric matter northward after it wasdischarged into the atmosphere: hut the shocks which happened,in the northern part of Scotland (viz. about Crief and Comrie inPerthshire) were not followed by thunder to the southward; be-cause the electric matter, though discharged into (he atmosphere,cannot return to the south without first going north, and rising upinto the higher regions.” The Encyclopedists , however, ac-knowledge that, “in the earthquakes in Calabria in 1783, there weresome circumstances which seem to militate against tliis theory.The most remarkable of these is their attacking the places situatedon the plain, much more than those which stood on the highergrounds. In a memoir on this earthquake by M. Dolomicu, thatauthor endeavours to exclude electricity from having any share inthe matter: and ascribes the whole phenomena to steam occasionedfey the rains of 1782—3, accumulated in caverns under Calabria ,and heated by the fires of -Etna. But not to mention other evi-vol. n. —no. 70.

deuces, a single circumstance, which M. Dulomieu itimself men-tions, is a sufficient proof of electricity being concerned ; and thatis the presentiment which animals had of its approach. “Thepresentiment of animals (says he) at the approach ot earthquakes, isa singular phenomenon, and which cannot fail to surprise us somuch the more, as we know not by what organs it is communicatedto them. Every species of animals experience it, especially dogs,geese, and poultry. The bowlings of the dogs in the streets ofMessina were so loud, that orders were issued to kill them.” Now,we know, that many animals have a presentiment of a changeof weather; which may happen either from a change of the den-sity of the atmosphere, or from some alteration in its electricity :but steam pent up in the bowels of the earth could affect no ani-mal until it began to exert its effects. Sir William Hamilton like-wise informs us, that geese seemed more affected by this causewhen in the water than out of it; which may easily be explainedupon electrical principles, but not at all, at least not without themost extravagant suppositions, by steam pent up in caverns no-body knows where. Again, it is evident, that M. Dolomieu’shypothesis is supported in the worst manner imaginable, viz. byarguing from things unknown to what we see; but the truemethod of argument always is from what we see to things unknown.By this error he lias made choice of causes which cannot possiblyanswer the purpose. Let any quantity of water be poured into thefocus of mount zEtna; nay, let the sea itself break into it: theconsequence could only have been what happened in 1755, viz.not an earthquake in Calabria , but a vast effusion ol boiling waterfrom the top of the mountain itseif. Nature here made the ex-periment; and we have no reason to imagine that any other con-sequence would have followed, though it had been repealed everso often. Our author seems also to have forgot, that aqueoussteam is capable of condensation, and that when it is admitted intoa cold place it instantly loses its expansive power. Let us sup-pose caverns upon caverns extended in any way he pleases: thegreater their bulk, the more will he be embarrassed; for thus thesteam would have room to circulate ; and far from producing thosedreadful convulsions, must have returned quietly into water, with-out being able to stir the earlii in the least. It would appear in-deed, that the power of aqueous steam is very much over-ratedboth by M. Dolomicu and other writers. As Nature, or ratherthe Autiior of Nature, does nothing m vain, it may not lie im-proper to consider, what uses earthquakes may he supposed to an-swer in the general system. As they are the effects of the veryhighest natural power, it cannot be supposed, that they are pro-duced merely for the purposes of destruction ; and, on the otherhand, as they certainly do a great deal of mischief, it seems as dif-ficult to assign any benevolent purpose. It is thought, indeed,that earthquakes are the means by w hich Nature raises mountainsand land from the bottom of the sea; but this can never be ad-mitted. We have many instances of mountains being swallowedup and lo.-t by earthquakes, but not a single well attested one of amountain being raised by them; and even when volcanoes aretaken into the account, by which some mountains and islands havecertainly been raised, the balance appears against them, and moreland appears to have been sunk by them than ever was raised, kseems most probable, therefore, "that earthquakes are accidental,and that the mischief tliev do is only to prevent a greater evil.Tliis we see takes place throughout the whole system of nature.Thunder and lightning, violent rains, storms of wind, 8cc. are allproductive of much damage on certain occasions; but we by nomeans suppose these pluvnomena to take place merely for the de-struction ; and therefore we name such effects accidents. To thesame account, on a larger scale, must we place earthquakes ; andit only remains to consider, what are the disa iters still more terriblethan earthquakes, which we should have occasion to. dread did theynot interpose to prevent them. These evils are naturally to bedreaded from any general commotion of the electric fluid dispersedthrough the whole globe of earth. That it does pervade it to thecentre, is what we can have no reason to doubt; but in the inter-nal parts it seems to lie dormant, or to be employed in operationswhich never manifest themselves to us. Towards the surface it isset in motion by the light of the sun. This produces a constantcurrent through the bowels of the earth from the equator towardsthe poles; for as the equatorial parts absorb more of the light thanthose farther S. or N. it must naturally be driven out in the northernand southern regions in proportion tel the quantity absorbed at the3 N equator.