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globe; and these we conclude to be the effects of fuch a power precifely as that about which we now inquire. Volcanoes are thus confidered as the proper discharges of a fuperfluous or redundant power; not as things accidental in the course of nature, but as ufeful for the fafety of mankind, and as forming a natural ingredient in the conftitution of the globe.

dies, proper traces of the manner of their production; and things which may be examined with all the accura→ cy, or reafoned upon with all the light, that fcience can afford. As it is only by employing fcience in this manner, that philofophy enlightens man with the knowledge of that wifdom or defign which is to be found in nature, the fyftem now propofed, from unquef-` tionable principles, will claim the attention of fcientific men, and may be admitted in our fpeculations with regard to the works of nature, notwithstanding many steps in the progrefs may remain unknown.

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The doctrine is then confirmed, by examining this earth, and by finding every where, befide the many marks of ancient volcanoes, abundance of fubterraneous or unerupted lava, in the bafaltic rocks, the Swedish trap, the toadstone, the ragstone, and whinstone By thus proceeding upon inveftigaof Britain and Ireland, of which parti- ted principles, we are led to conclude, cular examples are cited, and a defcrip- that, if this part of the earth which tion given of the three different shapes we now inhabit had been produced, ́ in which that unerupted lava is found. in the courfe of time, from the mate The peculiar nature of this fubter- rials of a former earth, we fhould, in raneous lava is then examined; and a the examination of our land, find daclear diftinction is formed between this ta from which to reafon, with regard mineral rock and the common volca- to the nature of that world which nic lavas. had exifted during the period of time in which the prefent earth was forming; and thus we might be brought to understand the nature of that earth which had preceded this; how far it had been fimilar to the prefent, in producing plants and nourishing animals. But this interefting point is perfectly afcertained, by finding abundance of every manner of vegetable production, as well as the feveral fpecies of marine bodies, in the ftrata of our earth.

Laftly, The extenfion of this theory, refpecting mineral ftrata, to all parts of the globe, is made by finding a perfect fimilarity in the folid land thro' all the earth, although, in particular places, it is attended with peculiar productions, with which the prefent inquiry is not concerned.

A theory is thus formed, with regard to a mineral fyftem. In this fyftem, hard and folid bodies are to be formed from foft bodies, from loofe or incoherent materials, collected together at the bottom of the fea; and the bottom of the ocean is to be made to change its place with relation to the centre of the earth, to be formed into land above the level of the fea, and to become a country fertile and inhabited.

That there is nothing vifionary in this theory, appears from its having been rationally deduced from natural events, from things which have already happened; things which have left, in the particular conftitutions of bo

Having thus afcertained a regular fyftem, in which the prefent land of the globe had been first formed at the bottom of the ocean, and then raifed above the furface of the fea, a queftion naturally occurs with regard to time; What had been the space of time neceffary for accomplishing this great work?

In order to form a judgment concerning this fubject, our attention is directed to another progrefs in the fyftem of the globe, namely, the de ftruction of the land which had preceded that on which we dwell. Now,

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for this purpofe, we have the actual decay of the prefent land, a thing conftantly tranfacting in our view, by which to form an estimate. This decay is the gradual ablution of our foil, by the floods of rain; and the attrition of the shores, by, the agitation of the waves.

If we could measure the progrefs of the prefent land, towards its diffolution by attrition, and its fubmerfion in the ocean, we might difcover the actual duration of a former earth; an earth which had fupported plants and animals, and had fupplied the ocean with thofe materials which the conftruction of the prefent earth required; confequently, we should have the meafure of a correfponding space of time, viz. that which had been required in the production of the prefent land. If, on the contrary, no period can be fixed for the duration or deftruction of the prefent earth, from our obfervations of thofe natural operations, which, though unmeasurable, admit of no dubiety, we shall be warranted in draw ing the following conclufions: 1, That it had required an indefinite space of time to have produced the land which now appears; adly, That an equal space had been employed upon the conftruction of that former land from whence the materials of the prefent came; laftly, That there is presently laying at the bottom of the ocean the foundation of future land, which is to appear after an indefinite space of time.

But as there is not in human obfervation proper means for meafuring the wafte of land upon the globe, it

is hence inferred, that we cannot ef timate the duration of what we fee at prefent, nor calculate the period at which it had begun; fo that, with refpect to human obfervation, this world has neither a beginning nor an end.

Befides this phyfiological defcription, an endeavour is alfo made to fupport the theory by an argument of a moral nature, drawn from the confideration of a final caufe. Here a comparison is formed between the prefent theory, and those by which there is neceffarily implied either evil or diforder in natural things; and an argument is formed, upon the fuppofed 'wifdom of nature, for the juftnefs of a theory in which perfect order is to be perceived. For,

According to the theory, a foil adap ted to the growth of plants is necef. farily prepared, and carefully preferved; and, in the neceffary wafte of land which is inhabited, the foundation is laid for future continents, in order to fupport the fyftem of this li ving world.

Thus, either in fuppofing nature. wife and good, an argument is formed in confirmation of the theory, or, in fuppofing the theory to be just, an argument may be established for wifdom and benevolence to be perceived in nature. In this manner, there is opened to our view a fubject interesting to man who thinks; a fubject on which to reason with relation to the fyftem of nature; and one which may afford the human mind both informa tion and entertainment.

Abstract of an Effay on Inftinct, read in the Royal Society of Edinburgh, up on the 5th of December 1785.

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By Mr W. Smellie.

want of fuccefs may be referred to different caufes; to want of attention to the general economy and manners of animals; to mistaken notions concerning the dignity of human nature;

and, above all, to the uniform endeavours of philofophers to distinguish inftinctive from rational motives. Mr Smellie endeavours to fhew that no fuch diftin&tion exists, and that the reafoning faculty itself is a neceffary refult of inftinct.

He observes, that the proper method of inveftigating fubjects of this kind, is to collect and arrange the facts which have been discovered, and to confider whether these lead to any general conclufions. According to this method, he exhibits examples, Firft, of pure inftincts: Secondly, of fuch instincts as can accommodate themselves to particular circumstances and fituations: Thirdly, of fuch as are improveable by experience or obfervation: And, laftly, he draws fome conclufions.

By pure instincts are meant fuch as, independently of all inftruction or experience, inftantaneously produce certain actions, when particular objects are prefented to animals, or when they are influenced by peculiar feelings. Such are, in the human fpecies, the inftinct of fucking, which is exerted by the infant immediately after birth, the voiding of fæces, the retraction of the mufcles upon the application of any painful ftimulus. The love of light is exhibited by infants, even fo early as the third day after birth. The paffion of fear is discoverable in a child at the age of two months.

Among the inferior animals, there are numberless pure inftincts. Caterpillars fhaken off a tree in every direction, turn immediately to the trunk, and climb up. Young birds open their mouths on hearing any noife, as well as that of their mother's voice. Every fpecies of infect depofits its eggs in the fituation moft proper for hatching and affording nourishment to its future progeny. Some fpecies of animals look not to future wants; others, as the bee and the beaver, are endowed with an instinct which has the appearance of forefight. They conftruct magazines,

and fill them with provifions. Bees difplay various remarkable inftincts. They attend and feed the female or queen. When deprived of her all their labours ceafe till a new one is obtained. They construct cells of three different dimenfions; for working bees, for drones, and for females; and the queen, in depofiting her eggs, puts each species into its appropriated cells. They deftroy all the females but one, left the hive fhould be overftocked. The different instincts of the common bee, of the wood-piercing bee, and of that fpecies which builds cylindrical nefts, with rofeleaves, are very remarkable.

Equally fingular are the inftincts of wafps, and ichneumon flies, which, though they feed not themselves upon worms, lay up ftores of these animals for the nourishment of their young.

Birds build their nefts of the fame materials, and in the fame form and fituation, though they inhabit very different climates. They turn and shift their eggs, that they may be equally heated. Geefe and ducks cover up their eggs till they return to the neft. The fwallow folicits her young to void their excrement over the nest, and affifts them in the operation. The fpiders, and many infects of the beetlekind, when put in terror, counterfeit death. This is not, as has been fuppofed, a convulfion or ftupor, but an artifice; for when the object of terror is removed, they recover immediately.

Of instincts which can accommo→ date themfelves to peculiar circumftances and fituations, many inftances may be given from the human fpecies; but thefe being improveable, fall more properly under the third clafs.

Thofe animals are most perfect, whofe fphere of knowledge extends to the greatest number of objects. When interrupted in their operations, they know how to resume their labours, and to accomplish their purposes by different means. Some animals have no other power but that of contracting or ex

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tending their bodies. But the falcon, the dog, and the fox, pursue their prey with intelligence and addrefs.

In Senegal, the oftrich fits upon her eggs only during the night, leaving them in the day to the heat of -the fun. At the Cape of Good Hope, where the heat is not fo great, fhe fits upon them day and night. Rabbits, when domefticated, are not inclined to burrow. Bees augment the depth of their cells, and increase their number, as occafion requires. A wafp carrying out a dead companion from the neft, if he finds it too heavy, cuts off the head, and carries out the load in two portions. In countries infefted with monkies, birds, which in other countries build in bushes or clefts of trees, fufpend their nefts at the end of flender twigs. The nymphæ of water-moths, which cover themselves with cafes of ftraw, gravel, or fhells, contrive to make their cafes nearly in equilibrium with the water: when too heavy, they add a bit of wood or ftraw; when too light, a bit of gravel. A cat, when shut into a closet, has been known to open the latch with its paws.

The third clafs of inftincts comprehends all those that are improveable by experience and observation.

The fuperiority of man over the other animals, feems to depend chiefly on the great number of instincts with which he is endowed. Traces of every instinct which he poffeffes are discoverable in the brute-creation, but no particular fpecies enjoys the whole. On the contrary, moft animals are limited to a fmall number. This appears to be the reafon why the inftincts of brutes are stronger, and more fteady in their operation than thofe of man, and their actions more uniform.

Moft human instincts receive improvement from experience and obfervation, and are capable of a thousand modifications. One instinct counteracts and modifies another, and often extinguishes the original motive to

action. The inftinct of fear is often counteracted by ambition and refentment: The inftinct of anger, by fear, by fhame, by contempt, by compaffion. Of modified, compounded, and extended inftincts, there are many examples. Devotion is an extenfion of the instinct of love, to the first Cause or Author of the Univerfe. Superftition is the instinct of fear extended to imaginary objects of terror. Hope is the inftinct of love directed to future good. Avarice is the inftinct of love directed to an improper object. Fear is likewife an ingredient of this attachment. Envy is compounded of love, avarice, ambition, and fear. Sympathy is the inftinct of fear transferred into another person, and reflected back upon ourselves. In this manner all the modified, compounded, or extended paffions of the human mind, may be traced back to their original inftincts.

The instincts of brutes are likewife improved by obfervation and experience. Of fuch improvement, the dog, the elephant, the horse, the camel, afford numerous and strong inftances.

From thefe and other examples, given of the different classes of instinct, Mr Smellie argues, that inftinct is an original quality of mind, which, in man, as well as in other animals, may be improved, modified, and extended, by experience.

Senfation implies a fentient principle or mind. Whatever feels, therefore, is mind. Of course, the lowest fpecies of animals is endowed with mind. But the minds of animals have very different powers; and these powers are expreffed by peculiar actions. The structure of their bodies is uniformly adapted to the powers of their minds; and no mature animal attempts actions which nature has not enabled it to perform: The instincts, however, of animals, appear often previously to the expanfion of those instruments which nature intended they should employ. This view of inftine

is fimple: It removes every objection to the existence of mind in brutes, and unfolds all their actions by referring them to motives perfectly fimilar to thofe by which man is actuated. There is perhaps a greater difference between the mental powers of fome animals, than between thofe of man and the most fagacious brutes. Inftincts may be confidered as fo many internal fenfes, of which fome animals have a greater, and others a fmaller number. These fenfes, in different fpecies, are likewife more or lefs ductile; and the animals poffefling them are, of course, more or lefs fufceptible of im proving, and of acquiring knowledge. The notion that animals are machines, is therefore too abfurd to merit refutation. Though not endowed with mental powers equal to thofe of man, they poffefs, in fome degree, every faculty of the human mind. Senfation, memory, imagination, the principle of imitation, curiofity, cunning, ingenuity, devotion, or respect for fuperiors, gratitude, are all difcoverable in the brute-creation. Every fpecies too has a language, either of founds or geftures, fufficient for

the individuals to communicate their wants to each other; and some animals underftand in part the language of man. The language of infants is nearly on a par with that of brutes. Brutes, without fome portion of reafon, could never make a proper ufe of their fenfes. But many animals are capable of balancing motives, which is a pretty high degree of reafon. Young animals examine all objects they meet with, and in this investigation they employ all their organs. The first periods of their life are dedicated to ftudy. When they run about and make frolicfome gambols, it is nature sport ing with them for their inftruction. Thus they gradually improve their faculties, and acquire an intimate knowledge of the objects that furround them. Men who, from peculiar circumftances, have been prevented from mingling with companions, and engaging in the different amufements and exercifes of youth, are always aukward in their movements, cannot use their or gans with eafe or dexterity, and often continue, during life, ignorant of the most common objećts.

Defcription of the Grotto of the Fairies at St Bauzile, near the town of Ganges, in the Cevennes. By M. Marfollier *.

NATURE prefents fo many which teaches him how little he

knows.

beautiful objects to our view, that we never confider thofe fhe con- Of thofe objects that most deserve ceals from us as worthy of our atten the attention of the curious observer, tention. Avarice, indeed, with un- mountains feem to be the chief; thofe ceafing eagerness ranfacks the bowels vaft refervoirs that attract and imbibe of the earth; and the Naturalift, with the waters of the clouds, that purify nawearied industry, explores the hid- and tranfmit them through a thou den receffes of the globe. Fofile fand fubterraneous channels; thofe fhells, petrified wood, and volcanoes, bare and barren rocks, the deformity are fources from which we draw new of which feems to announce the de additions to our knowledge; and it is crepitude of nature, afford ample scope by the continued exertions of thefe for obfervation. Who would believe labours and ufeful refearches, that man that thefe interefting objects fometimes as attained that degree of wisdom conceal others ftill more interefting ?. VOL. VII. No 39. Bb *Recueil amufant de voyages en vers & en profe,

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