tion of reafon; and animais have lately been difcovered to which the electric fluid ferves as a medium of fenfe through organs calculăted to exite it, and to receive and convey its impreffions. But there are few objects we can study that are more fubtle and obfcure than the influence of one living body on another. There is a familiar infance of the great fublety of animal effluvia, and alfo of the fineness of fenfe in a dog's being able to trace his mafter through crowds, and at a great diilance; and we can conceive that infectious matter may adhere, and be communicated in a fimilar manner. We endeavoured to illustrate the great obfcurity of its operation by an allufion to generation, digeftion, and other ́animal functions, with which it is equally abfcure and inexplicable. It is fimilar to generation in this, that its influence does not pass from one fpecies of animal to another; for the poifon of the plague, that of the finall-pox, that of fever, and the venereal difeafe, do not affect brutes, nor do the infectious difeafes of brutes affect different fpecies of them, nor the human fpecies. The only exception to this, that we know of, is the bite of a mad dog. * From thefe facts, and alfo from what was formerly mentioned of contagion not affecting indifcriminately all that may be expofed to it, it would appear that fome nice coincidence of circumftances is neceffary to modify an animal body, fo as to receive its action. There must be a fort of unifon, as it were, or fympathy betwixt different living bodies, fo as to render them fufceptible of each other's influ ence. It is none of the leaft curious facts with regard to infection, that, there are fome fpecies of it by which the body is liable to be affected only once in life. When this is confidered, it is indeed conformable to what happens in the courfe of the difeafe itfelf; for, unless there was in the body a power of refifling it, there could be no fuch thing as recovery. Where the difeafe actually exifts, the continued prefence of the poison, which is alfo infinitely multiplied, would infal libly destroy in all cafes, unless the living powers were to become infenfible to it +. It is of the greatcft confequence to afcertain the extent of the influence of infection, for the means of avoiding and preventing it will very much depend upon this. It is now known, that infection extends itfelf to a very finall distance. There are, indeed, fome morbid poifons, fuch as that of the bite of a mad dog, and that of the veneral disease, which require actual contact to make them take effect. Others are more volatile, and feem to be inhaled by the breath, or abforbed by the skin, but thefe do not extend far. That of the plague does not reach above a few yards, and that of the distance *Mr. Hunter,s Experiments. + Mr. Hunter's Lectures. It is related by the travellers into Turkey, that the Chriftians fave themfelves from it, merely by fhutting themfelves up in their houses, fmall-pox and of fevers, is probably equally limited. This difco very is very valuable, by afcertaining the limits of danger; for when a perfon imagines he runs the fame rifk when at a connderable diftance from the feat of difeafe, as if he were in contact with the perfon affected; he will be apt to expofe himfelf unneceffarily to the infection. It seems to be owing to, the ignorance of the extent of its influence, that the plague has in general been fo fatal; for in confequence of the opinion that the whole furrounding atmosphere was affected it was vainly attempted to purify it by large fires in the open air, inftead of trufling to the feparation of the tick, fo as to avoid their near approach, and to the confinement of thofe who are in health to their own houfes, which are all the precautions neceffary to prevent its progrefs. There is reafon to think, that the open air very foon diffipates and renders inert all infections of the volatile kind, and of course the warmer the air is the more readily it will have this effect. It is accordingly obferved, that infection is much lefs apt to be generated about the perfons of men, and that it adheres to them for a much lefs pace of time in a hot climate than in a cold or temperate one. This is a remark, which, fo far as I know, has not been made by any author; and, till obfervation fuggefted it to me, I fancied the reverfe to be the truth. I have feen fo many inftances of filth and crowding in fhips and hofpitals in the West Indies, without contagion being produced, and which in Europe could hardly have failed to produce it, or to render it more malignant, that I am convinced there is fomething in tropical climates unfavourable to the production and continuance of infectious fevers*. The fhips which bring this fever from. Europe in general get rid of it foon after arriving in a warm climate; and nothing but the highest degree of neglect can continue or revive it, The appendix to this part exhibits a concife view of the moft material obfervations contained in it, and merits the attention of every medical reader. Part 3d. contains the description and treatment of the diseases moft frequently occuring in hot climates. This part is executed with the fame ingenuity and ability as the foregoing. The account of Delirium, in particular, and his defcription of the yellow fever are drawn in a very mafterly manner. The houses, and the inhabitants, who fleep on the open roofs of the houfes, do not catch it even from thofe of the adjacent buildings, though the wall that feparates them is of no great heighth. * A fact, related in Anfon's voyage, is alfo ftrongly in proof of the fame opinion. When the rich Spanish prize was taken, it was neceffary to crowd the prifoners into the hold, for fear of an infur rection, which was to be dreaded from their number; yet, when they arrived in China, none of them had died, nor had any difeafe broke out. They fuffered only in their looks, being wan and ema ciated to a great degree. The fubject of the book before us is interefting to the public and to the legiflature. The British navy is the glory and the palladium of the empire. If the flock of mariners were to be exhausted or diminished, the lofs could not be repaired by the most flourishing state of the public finances; for money would avail nothing when numbers of able and healthy men were not be found, the real refources of a state, and the true finews of war. The fituation of mariners in another view, entitles them to our humanity and attention. They have parted with the dearest and most valuable prerogative of Englishmen, their LIBERTY; it is their character to be brave and intrepid, but thoughtlefs and negligent of their own intereft and welfare; the hardships and difeafes to which they are expofed wear out their conftitutions ten years before the rest of the laborious part of mankind; humanity and duty, therefore, as well as intereft and policy, call on the public to adopt every plan of improvement which is calculated to meliorate their fituation, and to prevent, as well as repair, the ravages of difeafe. We are, therefore, highly indebted to Dr. Blane for his valuable obfervations on the diseases incident to feamen. He has availed himself of the discoveries of others, and added obfervations of his own. He fhews an acquaintance with antient as well as modern fcience, but is never mifled by hypothefis or theory; nor wanders into the paths of fpeculation from the fure road of induction from facts, A few rafh or hazardous affertions do not detract from the general merit of the work. The ftyle is perfpicuous and neat, and when the subject will admit, it is elegant. ART. XII. Efays on the Intelle&ual Powers of Man. By Thomas Reid, D. D. F. R. S. Profeffor of Moral Philofophy in the Univerfity of Glafgow, 4to. 11. 5s. boards. Bell, Edinburgh. Robinfon, London. 1785. L [Concluded from our laft.] ET us now fuppofe that with all our faculties of reafoning, we had been conftituted without the fenfe of fight, the word idea would have had no exiftence, our knowledge or information would have been infinitely cir cumfcribed. The world; by which we mean all that we know or perceive of the univerfe, and a very fmall portion it would have been, would have appeared quite different to us from what it does now. A different fyftem of language would have been conftituted, and different fyftems of philofophy established. Even with their diminutive portion of knowledge, men would have formed theories con cerning the cerning the univerfe and their own minds; and embittered difputes would have arifen concerning the nature of the Su preme Being, and the laws by which he governs the world. We may conceive other beings endowed with powers as much fuperiour to our faculty of feeing, as that faculty is fuperior to any or all of the other fenfes; and other laws of nature may be difcovered that would appear as aftonishing to contemplating mind, and as little allied to the laws now known; as the power of gunpowder and mephitic air, or that of electricity and magnetifm, must have appeared to the philofophers of antiquity. Such being the uncertainty of metaphyfical fpeculation, arifing from the limited powers, and the varying views of mankind, Dr. Reid would perhaps have done fome fervice to the caufe of truth, if he had contented himfelf with pointing out the weak places of what he calls the ideal philofophy: for as ignorance is better than error, he does mankind a fervice who brings them back from error to a fenfe of their ignorance. But, when he talks of belief, knowledge, judgment, accompanying and mixing with fenfation, perception, memory, and other operations of the mind that are contradiftinguished from acts of the intellect by all men who have ever philofophized before him, and which are indeed different from the operations of the intellect, if by intellect we mean that faculty which is converfant, and difcerns the relations between one terni and one propofition and another; what does he elfe than confound judgment, with fenfe and inftinct, and level all operations of the mind into one? The mind indeed may be fimple in itfelf, but we diftinguish its operations from one another, according to the different fubjects upon which its power is exerted. The fyftem of Defcartes, Malebranche, and Locke, may be circumfcribed, may be imperfect, and in part, or in whole erroneous. This imperfection and error, if they exift, will probably be difcovered in fome future and diftant period of fociety, when the laws of nature fhall be more fully difcovered, when her fecrets fhall be revealed, and new ideas fhall afford new points of comparifon, and the enlarged powers of the mind fhall grafp and take in a wider and therefore jufter view of the works and ways of God. But the question is, whether with our prefent powers, and our prefent knowledge, there is any thing in the philofophy of the writers juft mentioned that offend against the laws of reasoning of reafoning by reflection, in a demonftrative manner where that can be done; or by analogy, as in other cafes, where it cannot? Now we fee darkly as through a glafs, Afterwards ENG. REV. Dec. 1785. perhaps, F f perhaps, we fhall fee more clearly. But in the mean time the twilight or rather the dawn, the faint adumbration of knowledge that we have, or are capable of attaining, is not to be rejected, for there are degrees of knowledge. A traveller, returning from fome diftant country, where he has met with fome object which he cannot refer, with exactness, to any of the claffes, orders, or fpecies of things with which we are acquainted, defcribes it as well as he can, by telling what it is like. And does he not by thus defcribing the object, communicate a degree of information concerning it? On the whole, the publication before us, appears to be an expanfion of our authors enquiry into the human mind. And in both thefe performances Dr. Reid appears to us to have carried the expulfion of analogy even to a fceptical length; fince incongruity, if not the fame thing, has confequences fimilar to fallacy. A perfon who has loft his way, and bewildered himself in the night, ftill retains his fenfes of feeing and hearing; but they are of no ufe to him: they are not annihilated, but they may be faid to be null fince he cannot make use of them, as there is no medium of communication between them, and the external objects of which he wishes to be informed. In like manner, if there is nothing prefent to the mind, or, in other words in the mind fimilar to external objects, there is fuch an incongruity between the one and the other, as refembles the impenetrable darkness of night which intercepts all communication between the traveller's fenfes and the objects he longs to behold or converse with. Dr. Reid, by infifting fo totally, both exprefsly and implicitly, on the hypothefis, that nothing external has the leaft affinity with any thing either in or belonging to the mind, any more than a tree has with anger or forrow, has gone farther than either his mafter Buffier, or his follower Beattie. He has pushed the general fyftem common to them all, to its juft confequences: but, by fo doing, his acuteness and ingenuity have only served to fhew the abfurdity of it. If we may hazard a conjecture, perhaps Dr. Reid derived the firft hint of his whole metaphyfical theory from Bifhop Berkeley, who maintains that we have no ideas of fpirits; and that we can think, and fpeak, and reafon about them and about their attributes without having any ideas of them,"-"If this is fo, my Lord, fays Dr. Reid, what fhould hinder us from thinking and reafoning about bodies and their qualities, without having ideas of them."* *See Inquiry Chap. VH. Mr |
