and deviations from the general plan; The furface of this is remarkably uneven. In confequence of which difpofition, not only a greater number, but alfo different kinds of animals and vegetables find room on it, and fituations peculiarly adapted to their different conftitutions: fome thriving beft on mountains, fome on hills, others in flat countries, and others again in vales and hollow fituations. I do not mean here to affert, that this is the fole end and purpofe of the earth's furface being formed with fuch inequalities. For this very difpofition of it occafions likewife the formation of shade; produces fprings (b) and rain (c), keeps the water in a continual circulation about the earth (d), and has many other important ufes in the economy of nature. The views of Providence are always effected by the feweft means poffible. In every department of Nature's works each co-operates and gives force to the other; and all unite to produce the effects requifite to the continuation and perfection of the economy of the whole fyftem. To this, the number of inhabitants greatly contributes: accordingly, we find the ftricteft economy practifed with regard to room. As much as the earth's furface is enlarged by its inequalities, yet fill this would not fuffice; if the deficiency were not made up by trees. One fingle tree, which does not occupy more than a quare foot or two of the furface, is equal in this refpect to many thoufands of plants. By this means what a multitude of quadrupeds, birds, and infects are lodged and fupported; for which fo trifling a fpot of earth could not otherwife poflibly afford either refuge or nourishment? Now, if we reckon up the space thus gained on the earth's fuperficies by the intervention of woods and groves, it will appear a matter of the highest importance when confidered in this light, (b) § even fetting afide the degree of orna ment and other ufes arifing from thefe charming pleafure-gardens of Nature. It is likewife abfolutely neceffary, both for plants and animals, that they fhould be environed with a fluid adapted to their conftitution. For this pur pofe there are provided two different oceans: the one of water, occupying the lowest parts of the furface of the earth; the other compofed of a lighter matter, which furrounds this planet of our's on all fides, under the denomination of the atmosphere. In one or the other of thefe oceans all animated bodies are feverally diftributed; a very fmall number excepted, which enjoy the privilege of shifting from one to the other for a longer or fhorter time. To one portion of animals the bottom of thefe oceans is affigned for their conftant and perpetual abode; of this kind are thofe belonging to the clafs of worms, and the major part of quadrupeds exifting in the atmospheric ocean; and in the watery, the vaft multitude of zoophytes, corals, fnails, mufcles, fome of the amphibia, and fome others, chiefly fuch as being predatory animals, or living on carrion, are deftined to keep the bottom clean, by fecking their fubfiftence from off it. Others are endued with the power of floating up and down in the medium that furrounds them, as birds and infects in the air; and in the water, whales and moft other kinds of fish. And as flying fish are capable at times of rifing into the air; in like manner fea-gulls and water fowl have the faculty of diving into the water. Motion and change feem to be in the highest degree neceflary to the duration and continuity of nature's fyftem. In the whole corporeal universe we do not know a fingle particle that is at abfolute reft; but, not to go beyond the limits of our own habitation, let us, for a moment examine our own planet in this refpect. The earth revolves round its own axis once in 24 hours; by which means every point of its furface, excepting at the poles, is continually shifting its place, with a greater or lefs degree of velocity, ac(c) $118. (d) $68. cording 1 cording to its fituation Under the Line, at which part the motion is fwifteft; all bodies are carried on above 11 miles in a minute, though at the fame time, they do not change their place upon the earth's furface. But, befides this, the earth, with every thing that is upon it, is, in its yearly courfe, carried round the fun with fuch fwiftnefs, that at its mean diftance from that luminary it travels at the rate of 146 (Swedish) miles in a minute. We are not, however, fenfible of either of thefe violent motions, fince every thing about us is in like manner fubjected to them. It is in this cafe, juft the fame as in a fhip, the motion of which is not perceived by the perfon that is in her, but is merely inferred from the apparent motion of the fhore. When bodies change places with each other, in this cafe the change is more evident to the fenfes. Small rills uniting together make brooks, thefe form rivulets, and afterwards large rivers, which at length fall into the fea. But this is not all. Plants and animals have every where need of water for their nourishment. This is diffolved into vapours, which are condenfed into clouds; and thefe again are precipitated in the form of rain and dew, and what is not changed and altered in its way, falls again into the fea. Moreover, ebb and flood, ftorms, rivers, &c. daily put the water in motion. Neither (f) is the atmosphere more at reft. The moon muft neceffarily influence this likewife. Between the tropics there blows inceffantly an eafterly wind; and though in other places at times no motion is obferved, yet the variations of the barometer and thermometer fhow, that, notwithstanding this appearance, the air is by no means at reft. Eefides, the different kinds of meteors occurring in the atmosphere are further convincing proofs of the manifold changes operated in it. The furface of the earth is, in like manner, fubject to its alterations. Hard rocks are rent afunder (). Stones by degrees moulder and fall to pieces (o). Some places fink (p); others are covered with water (q); one part is raifed (r), while fome are deftroyed by earthquakes (); hills are washed away (t); vales filled up; moraffes are converted into firm land (r); what was formerly covered by the fea becomes dry ground, &c. Light and darkness, heat and froft, drought and rain continually fucceed each other (). And, fetting thefe afide, the inceffant variations in the temperature of the air, with respect to warmth, produce hourly, though often imperceptible changes in the particles and pores of bodies. If to these we add the motions occafioned by organic bodies, and those which they themselves undergo (u), we may in fome meafure comprehend the conftant changes to which all things are fubject. Man himfelf is fuppofed to wafte daily about two ounces and a half in substance, which quantity is abraded, or paffes off by perfpiration. This deficiency is fupplied by fresh particles; fo that in about ten years he is furnished with quite a new body (x). In fine, animals and plants are nourished, grow up, propagate their fpecies, die, and moulder into duít. Thus every thing is in motion, every thing is increafing or decreafing. In a word, to be born and to die, to fpring up and to difappear, is the fate of every thing by turns in this fublunary theatre. This, however, does. not happen, as at firft fight it may feem to do, without order or limitation. Every thing follows certain laws; all is ordained for certain purpose, all accords in the moft perfect manner to the praife of the Almighty artist. The intire connexion of things is, it must be confeffed, unknown to us: but from what is already difcovered, we can no longer doubt of the reality of this con nexion. Now, although every effect is produced according to certain laws; and Natural Philofophy has been at all times bufied in inquiring into these laws, Each Swedish mile containing above five and a half English. (f) 203. 217. (g) 111. 118. 58.84. (b)§ 100. (i) § 99. (k) § 102. (m) 111. 132. (n) § 48. 49. (0) § 148. (P) § 148. (2) § 150. (r) § 149. (1) $41. (*) § 138. 145. (*)§ 208. (1) § 134. (5) § 150. laws, and indeed in the last century has made amazing advances in the affair, nevertheless we cannot help acknowledging that we labour under a horrid degree of ignorance. Whitherfoever we turn our eyes, we are obliged at laft to ftop at fomething beyond our comprehenfion. Thus, on examining the contents of a mountain confifting of regular ftrata mixed with fhells, we may in a fuperficial way reprefent to ourselves, that different kinds of fubftances have been deposited there by the water with which the place was formerly covered, and that the cruftaceous animals having been bedded in along with them, in procefs of time all has grown haid together. But let us But let us confider this matter more accurately. In the ftony part of thefe ftrata we find veins of various kinds of metals; how came these here? In this part, too, we meet with different forts of cryftal. What force is it that governs thefe pellucid bodies, by virtue of which they fhoot always in the fame form? &c.- -We understand the nature of lightening better at prefent, than fifty years ago we had a right to fuppofe we should have done in a much longer fpace of time (y). Any one who had at that time maintained, that we should in thefe days be able to bring it down. from the clouds, and conduct it any where at pleasure, nay, even to counterfeit this terrible meteor, would without doubt have at least found the reward of his temerity in a mad-house. And knowing as we are in this matter, we muft ftill, however, confefs our ignorance of the internal conftitution of the electric fluid. Who could have imagined fome years ago, that fiefh fo far gone as to become offenfive to the fmell, and fall to pieces, could be made freth and palatable, an effect however, which every fmatterer in chemiftry now knows how to produce. We are likewife apprized of the reafon of this; but the internal compofition of thefe fubitances may remain a great while longer a fecret to us. A plant grows up from a fall feed, which it often exceeds many millions of times in bulk; it draws up its nou rifhment between its woody fibres, bloffoms, and bears fruit. Some have withal the power of voluntary motion, and contract themselves, when they are touched; others catch and detain fmall infects. The feedcapfules are in a manner particularly curious, contrived to diftribute the feed according to the purpofes of nature: but according to what laws is all this effected?--In the animal kingdom we find ftill greater caufe for wonder and admiration. Here, befides the power of increafing and multiplying their fpecies, the faculties of arbitrary motion, and of fenfation, further prefent themfelves to our obfervation. We know very well that the eye can difcern the pictures painted on the bottom of (b) it: that the ear takes in the vibrations and ofcillations of the air, &c. But what is fenfation? How is it performed? How is it that a practised ear can diftinguish fo many various tones as ftrike it at one and the fame time in alarge concert (e)? What is the reafon, that fuch quick undulations of the air, which follow each other with the greatest i rapidity, or elfe are made at precifely the fame time, what is the reason that they are not confounded together by this organ without diftinction? Whe is able to explain the propagation of that forry little animal, the book-louse, for many fucceffive generations without copulation? (e) Who can in a fatisfactory manner account for a crawling worm, with twelve eyes and fixteen feet, being changed into a flying infect with four wings and a thousand eves? Who is capable of inveftigating to their first principles the ftructure of animal bodies, the ufes of all their parts, the reafon of their different figure, and the like? Whence is it that fome kinds of fish are able to give the electric fhock in the open fea? And in what manner does the magnet act, when it entirely deprives them of this faculty? &c. &c. Here is an ocean of wonders which still remain unexplained. Many of them indeed may in procefs of time be refolved, and that, perhaps, against all expectation: but the fprings by which they are actuated, their nature, and (b)5203. (c) 203. (d) 212. (e) § 209. § (202. 216. (8) § 205. 3 (y) § 129. (~) § 105. 167. 205. 218. and mode of operating, are doubtlefs placed beyond the narrow circle of our horizon. No inftrument, any more than any of our external fenfes, can carry us beyond certain limits. It is true, that, by means of telescopes and microfcopes, we can difcern moft glorious fpectacles, fuch as no man heretofore even dreamed of: it is likewife probable that thefe inflruments may hereafter be brought to far greater perfection than they can boait of at prefent: but, from the very nature of things, this improvement cannot be carried beyond certain limits. The more a perfpective glafs magnifies, the fmaller is the field it takes in at one view, and fo much the more imperfect will be our view of the whole object. Thus it is in many other cafes; what is gained on one fide is loft on the other; and the pride of human wit muft in the end, how much foever fuch a confeffion may go against the grain, be brought to acknowledge its extreme weakness. What then are we to think of that arrogant felf-conceit, which undertakes to inform us in what manner every thing that exits upon the earth had its prefent conftitution and ftructure imparted to it by the laws of Nature? It is by no means my intention to reject hypothefes entirely; for though one incontrovertible experiment often gives more real light than a hundred hypothefes, yet thefe latter are of great utility. I will only mention here, that they ought always to be confidered as conjectures, and not as demonftrated truths; and that particular facts must not be wrefted in order to fuit them. Weare not even able to find out the principles of the primitive architecture of the Peruvians: on what grounds, then, can we hope to comprehend the admirable operations of Nature? Obfervation and experiment are the two genuine clues to be used in refearches into her works. Hypothefes are like a dim taper, by the glimmer of which we can fee to lay hold of the clues alluded to; but which leaves behind it, when these latter will not serve to conduct us any farther, a weak and enfure light, which frequently is more LOND. MAG. Oct. 1783. deceitful than the ignis fatuns itself. On the other hand, experiments made without view or connexion may be compared to the actions of a man groping in the dark. A difcovery made in purfuance of a well-digefted plan has infinitely more merit than one to which we have been led by accident, and which, without any forethought, the circumftances in which we were placed have, as it were, forced upon our obfervation and notice. Now, if in this our diminutive and contracted dwelling there exift fo many thousands of bodies endued with life, that we are abfolutely furrounded by them on all fides; if here fuch indefcribable differences and variations take place, in regard to fize, form, colour, nature, manner of living, propagation, &c.-fo many wonders and fuch a multitude of things which furpafs our comprehenfion: what must be the cafe in fo many thoufands of worlds fuperior to our earth in point of magnitude? What may be the fhape and properties of their rational inhabitants and of the other animals refident there? What is the ftructure and conftitution of thefe worlds? Differing in fituation, in the periods of their revolutions, and in feveral other circumftances, each of them requires a peculiar and appropriate economy, bodies of different natures, &c. but wherein this difference in the various parts of the mundane fyftem muft confift, it is beyond the limits of our capacities to determine. We are not acquainted even with the microfcopic worlds, or the minute animalcula which are in ifible to the naked eye, and which dwell all around us; what kind of cognizance, then, can we be fuppofed to have of the inhabitants of thofe worlds, of which we cannot even difcern the true figure through the beft telescopes. When, with due attention, we confiderall these things, we cannot poffibly avoid acknowledging the omnip tence, goodnefs, providence, and infinite wifdom of the Creator. O Lord, how manifold are thy works LITERARY ARTICLE REVIEW. XXIII. T HE Philofophical Tranfa&tions of the Royal Society of London, Vol. LXXII. for the Year 1782, Part II. London. Davis and Elmiley. (Continued from page 248.) IN our laft Mifcellany, we gave an account of the three firft papers in this volume. We fhall now proceed in our Review. IV. Proceedings relative to the Accident by Lightening at Heckington. (Read February 14, 1782.) In June, 1781, the Poor-houfe at Heckington, near Norwich, was fired by a ftroke of lightning, notwithstanding it was armed with eight pointed conductors. The Board of Ordnance received information of the accident, and, by a letter to the Prefident of the Royal Society, requested all the information relative to the fact, which had come to the knowledge of that learned body. It was, therefore, determined, that Dr. Blagden and Mr. Nairne fhould be requelled to take a journey to Heckington, in order to examine into the circumstances of the accident; and engage a draughtfman to make the requilite drawings. The report of these gentlemen was read to the council, on February 7, 1782, and then tranfmitted to the Foard of Ordnance. We fhall give the fubftance of this paper, as the accident was fingular, and the narration is authentic. When Dr. Blagden and Mr. Nairne arrived at Heckington, they found that fome part of the damages had been repaired. Seven months, indeed, had elapfed, fince the houfe had been ftricken by lightening. No material changes, however, had been made in the conductors, and they obtained a diftinct account of the feveral reparations, from the workmen. The building is in the form of the Roman letter H, and confifts of a center range and two flanks, and ftands on a gentle afcent. It has fome low buildings or offices annexed to the flanks, with a yard both before the houfe and behind: it is provided with eight chimneys. To each of thefe an iron rod was affixed, pointed at the upper end, tapering about ten inches to that point, and reaching between four and five feet above the tops of the chimneys. The rods were nearly fquare, with the angles juft rounded off. They meafured, upon a mean, about half an inch one way, and four tenths of an inch the other. These conductors were continued down the building, by a fucceffion of fimilar bars of iron, in general from fix to eight feet long, joined together by two hooks and a nut. The whole number reached above the chimneys, but only one of them was carried to the ground fingle. Three of them were fucceffively joined together, in a fingle rod, in one part of the building, and fo continued down. In another part, two of them met, and were united in the fame rod, as two more did in a third place. They were all faflened to the walls by ring ftaples. The fingle conductor was carried down the weft flank, till it came very near the ground, when it entered a fmall channel of brick work, through which it was continued under the pavement, into a narrow bricked drain, leading through the wall of a privy, into which the drain difcharges itfeif. Here it terminated in air, under the feat of the privy; while the folid work was in no placenearer it than three inches. This drain, though it flopes very ra pidly, muft fometimes be moift, as it received the foul water from the yard, and was near a water cock. The iron, in which the three conductors terminated, when it came near the bottom of the wall, was turned off into a fink, built of brick, into which it projected four inches, refting in contact with one of the bars of a grate, which is fitted into its fouth fide. then terminated in air. It 'The third termination, which was formed |