"High o'er his foes his hundred arms he rears, 87. Phanome electron is The object next in course is to exhibit an enumeration of na in which the most remarkable phenomena in nature in which the manifefted. prefence of electron is manifested. In pursuing this branch of the fubject it is not intended to notice every minute inftance in which electron is known to be an agent; but thofe extraordinary and prominent cafes only, where its effects are fuch as to command irresistible attention. 88. Electron The first remarkable phenomenon in which electron is manifefted manifefted to the fenfes of mankind, is that of lightning; the identity of which with electron we have seen to be a discovery belonging to our own country. in light ning. 89. Explanati non. In this phenomenon a fmall portion of electron, proon of this bably spherical in its fhape, but affuming the appearance of phænome- a line, from the velocity of its motion, and of a line with angles, either from the interpofition of conducting subftances in its courfe, or from fome unknown cause producing this peculiar motion, paffes out of one cloud in the atmosphere into another cloud, or out of a cloud in the atmosphere into the earth. 90. Nature of found. The found attending the motion of this portion of electron is called thunder; and in order to have an accurate idea of the manner in which it produces this effect it will be neceffary to bestow a little attention on the nature of found. Every object, moving through the atmosphere only, by difplacing its parts, produces a fmall degree of found; but when one body, immerfed in the atmosphere of the earth, moves from its pofition, and comes into contact with fome other body, a greater degree of found is occafioned. The collifion of the two bodies produces a vacuum in the atmosphere, and this is immediately clofed again by the attraction which the earth exerts upon all parts of it. The meeting of the parts of the atmosphere which have been thus forcibly disjoined, produces a wave, which pro 91. ftances which re ceeds from the place of the vacuum as a centre, to all parts of the atmosphere as a circumference, gradually diminishing as it recedes from the place of its origin. The wave is fimilar to that produced by the throwing of a ftone into water, with this difference only, that it is fpherical, and not merely horizontal. This wave, impinging on the tympanum of the animal ear, generates the sensation of found. The intensity of found is regulated by the four following Circumcircumftances. First, the velocity of the bodies, the contact of which produces the vacuum; according to which gulate the velocity is the fuddennefs of the reclosure of the disjoined intensity of parts of the atmosphere, and the velocity of the confe- found, quent wave. Second, in proportion to the fize of the bodies; according to which is the fize of the vacuum, and the fize of the confequent wave. Third, in proportion to the vicinity of the auditorial tympanum to the place of the vacuum; according to which is the fize and velocity of the wave, and the force with which it impinges on the tympanum, Fourth, in proportion to the density of the medium; according to which is the force with which the wave impinges on the tympanum, the velocity and distance being the fame. On this laft account in no medium, or in other terms in vacuo, there is no found, and a bell rung in the receiver of the air-pump; when exhausted of air, is filent; in a rare medium there is a faint found, as where a bell is rung in the receiver of an air-pump, into which has been admitted a much rarefied air; and in a dense medium there is an intense found, as where a bell is rung in water, into which the ear is immersed. 92. thunder is In the phænomenon of lightning, though the fize of Why the the vacuum produced is comparatively fmall, though the found of human ear is at a confiderable distance from the place of fo great. the vacuum, and though the vacuum is made in a medium lefs dense than that in which the ear is immerfed, yet the found is prodigious. This is owing entirely to the unexampled velocity of electron. In lightning the velocity is greater than in any other affignable phænomenon. The velocity of electron is fo great as to be literally incalculable; and there have been yet difcovered no poffible means of estimating it. 93. in detona tion. The nearest resemblance to the found produced by the Refembled paffage of a small sphere of electron out of one cloud into another, is that produced in the phænomenon of detonation. In detonation, oxygene, on the application of heat, is fuddenly attracted, out of the nitric, into the detonation combustible material; and the septic and carbonic gaffes are produced, which expanding with great rapidity dif place the parts of the furrounding atmosphere. The circumftances which increase the found are, that the size of the vacuum is large, on which account the fize of the wave produced by the reclosure of the disjoined parts of the atmosphere is alfo large; that the auditorial tympanum is in the vicinity of the place of the vacuum, on which account the fize and velocity of the confequent wave are great, and it impinges on the tympanum with greater force; and that the medium is of equal denfity with that in which the human ear is immersed. Hence, though the velocity with which the oxygene moves to the absorbing body may be less than that with which a sphere of electron moves out of one cloud into another, yet from every other circumstance being greater in degree the found produced is not diffimilar. 94. Lightning The flash and the found produced in the detonation of formerly gunpowder, fo exactly refemble the flab and the found fuppofed a produced by the paffage of a small sphere of electron out of gunpow. of one cloud into another, that previous to the æra of der. Franklin of America it was not doubted they were the fame. Men of learning therefore applied themselves, by a variety of ingenious theories, to account for the meeting of nitre, fulphur, coal, and heat, in the atmosphere, not fufpecting that in reality not one of thofe ingredients. had any concern in the operation; a striking proof into what important errors our extreme ignorance may fometimes betray us. 95. Different thunder, It is probable that the rolling found fometimes instanced founds of in thunder, proceeds from the paffage of a portion of electron from one place to another, through a feries of interpofed conductors, and those perhaps imperfect; while the fharp and coupé found proceeds from the paffage of a portion of electron from one object to another, through a clear space of atmospheric air, not containing any intermediate conducting fubftances. In those inftances where playful corrufcations are feen, without any, or with very little found, the electron is situated in a very rarefied medium. A cloud is frequently obferved in this fituation to exhibit repeated flashes, in very quick fucceffion, without any thunder. 96. The fecond remarkable inftance in which electron is Electron fubjected to the senses of mankind is in the phænomenon in the Au of the Aurora Borealis. manifefted rora Borea Nature of For the explanation of this phænomenon we are indeb- lis. ted to the genius of our countryman to whom we owe 97. that of the preceding. The Aurora Borealis is occafioned the Aurora by that thin atmosphere, which fuperincumbs the cold Borealis condenfed ftratum of air at the poles, becoming charged with electron. Finding no conducting fubftance to which to adhere, and fo infulated by cold and ice on every fidé that it cannot find the means of efcape, the electron in this rarefied medium plays as it were upon itfelf; fluctuating as the medium itself fluctuates, and governed by the varieties of rarefaction fucceffively taking place. This faint and beautiful light, this unabating and capricious restlessnefs, this roving about in sheets in every direction, are the principal characteristics which mark the Aurora Borealis. It is attended in general with no found, and feems to produce no effect worthy of remark, except that it affects the magnetic needle when in its vicinity. in meteors. 98. The third remarkable inftance in which electron is fub- Electron jected to the fenfes of mankind is in those atmospheric manifefted meteors, which are frequently feen traverfing the evening fky, fudden in their origin, fhort in their course, brilliantly luminous in their career, and fuddenly diffipated. 99. These meteors are, either folid fpheres of electron, or Nature of fpheres of conducting matter charged with electron, meteors. which by their rapid motion through that extensive mass of hydrogenous gas which fuperincumbs the common atmosphere, become brilliantly luminous; and affuming a direction to fome conducting matter in the atmosphere, on reaching it, the electron is discharged, fometimes with, fometimes without, fenfible found, and the luminofity disappears. Electron manifested Earthquake The fourth remarkable inftance in which electron is fubjected to the senses of mankind is in the phænomenon in the of the Earthquake. The Earthquake may be defined to be the paffage of a Definition portion of electron, from one place in the body of the earth, and effects to another. ΙΟΙ. of the Earthquake 102. Reality of it as an elec tric effect. 103. Defcription of the Earthquake as felt at Sea. It is ufually attended with the rolling found of thunder, with the fmell of electron, with an obvious prefentiment of it in animals, with the expanfion of water, with the luminofity of it when ejected from the furface of the earth, with an undulation in the surface of the earth itself, and fometimes with the difrupture and avulfion of its parts, thus producing a chafm, into which the human race, with the monuments of their induftry, are precipitated. It does not comport with the object of this work to enter into a history of the multiplied disasters and devastation, which have fometimes been produced upon the furface of this earth, by the agency of electron, in the phanomenon of the Earthquake. It is fufficient to obferve that electron is in this instance ftill more formidable and terrible an enemy than in lightning. If a decided teft were asked, to fatisfy the mind that the Earthquake is really an electric phænomenon, the following might be exhibited as a fatisfactory proof, among others ftrongly corroborative. The effects of the Earthquake are experienced at fea, as well as on land. Water conducts electron with great facility; and falt water is a far better conductor of electron than fresh. Those mariners, who have experienced the effects of an Earthquake at Sea, do not defcribe the affection of the veffel as fimilar to that which an object floating upon a body of water would fuftain, if the mafs of water received a fudden communication of motion. If an object is floating in a veffel of water, and a sudden ftroke is given to the veffel, imparting a motion to the whole mafs of water in it, we may readily imagine the fpecies of affection which the floating object would sustain. If the effects of an Earthquake, as experienced at sea, were in the leaft fimilar to fuch an affection, on the prefumption that a certain quantity of motion was imparted to the mafs of the water at fea, from the motion existing on land, the circumftance would afford no prefumption that electron was the caufe of the Earthquake. But the fenfation is entirely different. It is described to resemble a fudden arreftation, and cincture of the veffel, on all its parts, which are immerfed in the water, at the fame time. It has no refemblance to the affection produced on the vefiel by a fluent and fuddenly refluent mass of water. It has no refemblance to its impingement on a rock, or other foreign matter in the ocean; or to the ftroke of the remora. It is a motion which does |