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Dr. Cullen's hypotheses, that require for their support, at every step, the assumption of an indefinite principle, an imaginary "vis medicatrix natura," which truly is sufficient to explain, at pleasure, any thing or nothing. We moreover escape the dilemma of Dr. Rush, in his attempt to assign the reason "why excess in the force or frequency of the action of the "blood-vessels should succeed debility, and be connected for "days and weeks with preternatural debility in the muscles, 66 nerves, brain, and alimentary canal," for which the Doctor has utterly failed to account in a satisfactory manner. And we are extricated from the inconsistency of all other theorists in their fruitless labours to explain a disordered, unnatural, and morbid state of the body, on the principle of natural order and healthy action in the economy of life.

61. If I should fail in establishing this theory of fever, it will be some consolation to me to reflect, that I shall only share the common fate of all my predecessors in medicine: and with them I shall enjoy the satisfaction of having laboured to discover and to promulgate new truths, rather than to confirm and to propagate old errors.

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To the Editors of the Medical and Philosophical Journal and

GENTLEMEN,

Review.

The Author of the following Lecture, which is now sent to you for publication, had no idea, at the time it was written, that it would ever appear in print. This observation is not made to excuse any errors which it may contain, but to prevent a charge of plagiarism for not having marked every thing which is borrowed with inverted commas. These were thought unnecessary at the time the piece was written, as no person but the Author could have seen them, and his memory did not afterwards enable him to discriminate between what was borrowed and what was original. In the writers he quotes, most of the facts and opinions which are brought forward may be found; but as these are not generally known, they may not be unacceptable to your readers.

Yours, &c.

7. A. SMITH.

A LECTURE introductory to the second Course of ANATOMICAL INSTRUCTION in the College of Physicians and Surgeons for the State of New-York; delivered in that Institution, on Friday, the 11th of November, 1808, by J. AUGUSTINE SMITH, of the Royal College of Surgeons, London, and Professor of Anatomy and Surgery in the University of the State of New

York.

No flowers of rhetoric, no flights of fancy, Gentlemen,

grace the lectures of the Anatomist. Demonstration, his cold, his creeping, his constant companion, conducts her votaries to the temple of knowledge, by a route safe and certain, but unadorned. Her train is, indeed, seldom numerous; for men of brilliant imaginations and lively fancies scorn her slow and timorous progress, and soar at once into the regions of hypothe.

sis. But too often they find they have risen on waxen pinions, which, melting before the sun of truth, they fall into an ocean of oblivion or contempt. To avoid a similar fate, we shall never wander from our guide, in tracing the peculiarities of structure which distinguish the various races of men; a subject eminently calculated to interest the man of science of whatsoever denomination.

Before we begin the inquiry, it will be necessary to define a word which will frequently occur-the word race, as applied to the human species. It is not intended to imply by this word an original or radical distinction among men, but merely to express the fact, that differences do exist. These distinctions are now so obvious as to strike the most careless observer, and so great as to confound the most acute inquirer. While by one class of philosophers they are attributed to climate and other secondary agents, another, conceiving these causes inadequate to the effect, boldly assert the existence of distinct varieties of men. Before I examine these different opinions, I shall first fairly state the facts involved in the discussion. I shall not, however, bring forward every minute peculiarity which anatomists have detected, and which might be thought to exist in the brain of the dissector only, or to have arisen from some accidental circumstance; but I shall confine myself principally to those varieties of structure which are too obvious to be delusive, too constant to be fortuitous. I shall endeavour to prove that the anatomical structure of the European, whatsoever may be the cause, is superior to that of the Asiatic, the aboriginal American, and the African, or, at least, that it is farther removed from the brute creation. But I shall principally contrast the European and the African, because, being placed at the opposite extremes of the scale, the differences. between them are more numerous, and more strongly marked. Before we proceed to compare the various races of men with each other, we must point out the differences between man and other animals.

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Naturalists have arranged all living substances under two grand denominations, the animal and vegetable kingdoms. These they have subdivided into classes, orders, genera and species. Yet these divisions are the work of man, nơt of nature, for nature forms individuals only, and so gently does she glide from one class, genus, or species to another, so faint are the lines that separate even the kingdoms from each other, that it is impossible to say where the one ends and the other begins. “The water polypus," says Buffon, " may be considered as the "last animal or the first vegetable." "Yet, though the descent is constant, it is not uniform, for man is clearly distinguished from all other animals by his anatomical structure; some, however, resemble him much more nearly than others: among these the simiæ or apes hold the first rank, and among the apes the ourang outang stands next to man.

It was for a considerable time supposed that the human brain exceeded that of any other animal in size, but some of the cetaciæ far surpass man in this respect. It was then imagined that, compared with his body, his brain was larger than that of other animals; and so it is with regard to the whale, the bulk of whose body is yet larger than his brain, compared to that of the human subject; but not so with respect to some of the smaller animals, (the Canary-bird is one) whose brain, compared with their body, is larger than ours. Lastly, it has been found that of all animals hitherto dissected, the nerves of the human subject, compared with his brain, are the smallest. In the lowest order of animals there is no distinct brain, but merely a few nervous chords. But man differs from other animals more in the form than in the capacity of his cranium. This form is most conveniently measured and expressed by what is called the facial angle. This angle is formed by the intersection of two lines at or parallel to the inferior part of the nostril, one being drawn from the most projecting part of the forehead until it strikes the edge of the incisior teeth of the upper jaw, the other from the inferior part of the bony canal of the ear until it meets the other

at the place above mentioned. Sometimes it is called the facial line; in which case the lower line is always supposed horizontal, and the inclination of the other to it is meant. There is a very remarkable coincidence between the obtuseness of this angle and the intellect of the animal; but there is one source of error in its application, which must be pointed out. In all animals whose brain has a bony covering, there is a separation of the two plates or tables of the skull, as anatomists term them, just above the nose, forming what are called the frontal sinuses. These sinuses vary considerably in size, and it is evident where they are large they would cause a considerable projection of the forehead, without a corresponding elongation of the brain. This is remarkably the case with the elephant, whose facial angle is consequently very obtuse; and hence probably the great reputation he has acquired for intellect; his name, in the EastIndies, implying that he possesses reason.

In man this angle varies from 70° to 90°.† In the ourang outang it is 67°; Sapajou 658; Talapoin monkey 57°. In the Mandrils, which are the most mischievous of the monkey tribe, it is only 30°. In birds it is much more acute than in quadrupeds, particularly in the goose; and hence, perhaps, the proverbial stupidity of that animal. Another circumstance to bę attended to with regard to the heads of animals, is the relative proportion between the face and the cranium. Upon making a vertical section of the heads of the following animals, the proportions were, in the ourang outang one to two and a half; in the Sapajous one to two; in the Mandrils and in dogs they were nearly equal; whereas, in the horse the face is quadruple the size of the skull.‡

Man is the only animal that has a projecting bony chin. In those animals which most resemble him, it becomes gradually

* Cuvier.

The author has had an instrument made by which the angle can be measured with the greatest accuracy.

These proportions are taken from Cuvier's Comparative Anatomy.

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