and accent, it is necessary that the cavity of the mouth should be small, its boundaries regular and uninterrupted, and the communication between it and the nostrils free.

Now that is the very character of the mouth in Man. Provided with an arm and hand, free to execute all the objects of his will, man is under no necessity to use his mouth as the brute does. Being limited to manducation, the jaw-bones may be of small size and light construction, while the teeth may likewise be small, be set erect, and ranged in uniform, regular rows, so important for distinct articulation. On the whole, from the mouth being absolved, by the perfection of the hand, from performing more offices than those of mastication simply, the cavity admits of being diminished in size, the jaws and teeth of being reduced to moderate dimensions, and the whole form is suited in the most admirable manner for an organ of articulate language.

On looking to the skulls of different races of mankiud, it will be seen that Nature, in fashioning the mouth of man to be a speaking organ, has not departed from her usual course of carrying on the process of development by slow and gradual steps. Observe what a contrast exists between the skull of the Negro and that of the European, caused by the inordinately large size of the jaws and projection of the teeth in the former. The wellformed skull of the European is distinguished by having the jaws and teeth of comparatively diminutive size; while the cavities formed in the interstices between the bones of the face, at the brows and cheeks, and which communicate with the nostrils, to allow a free circulation of air round the chambers where sound is produced, being parts of the organ of Voice, are full and prominent.

Thus we perceive how the genius of the sculptors and painters of antiquity led them to discover a principle of beauty, in designing the human head, founded on a profound view of the relation existing between Man's physical structure and his mental constitution—the principle expounded in the first essay of this work. Regarding his supremacy over all created beings to be in virtue of his possessing a Mind, they looked for the signs of his superior organization, to those structures which minister most directly to the mind. The cranium was represented capacious and full, it being the part where the Brain, the seat of intellect,

man.

is lodged. But they studied, at the same time, the organ by which the operations of the intellect are embodied in Speech, and intercourse is established between the minds of man and The lower part of the face, including the jaws and teeth, which in brutes have such a preponderating size to enable them to seize and rend their prey, was made small and delicate; while the upper, composed of passages and chambers permeated by the air, and accessory to the organ of Speech, were expanded and elevated into due dimensions, so as to give them characteristic prominence.

Thus, in whatever view we study the development of the animal frame, new proofs present themselves of the final aim of all the modifications which we successively trace, being to confer upon man an instrument adapted to his intellectual nature-an organ of Speech. It is the fine adjustment of the various members of his body for that object, that renders his organization the most perfect in the animal kingdom. Additional strength is, therefore, given to the author's opinions that our conceptions of human beauty, both as regards the form of the head, and the moveable features, have a direct relation to the fitness of the structures for Speech, Voice, and Expression.

Such is a brief account of the leading parts of the discoveries made by the author of the volume, in that important part of the anatomy of the body--the Nervous System. He first established that the nerves of Motion are distinct from those of Sensation;—and that the nerves, generally, possess different endowments, according to the divisions of the brain or spinal marrow from which they arise. He then arranged the nerves of the whole body into three distinct systems, corresponding with the organs which they respectively control. The First class is

that composed of the Spinal Nerves and fifth Nerve of the brain; this class, he proved, bestows both motion and sensation on all the parts to which it is distributed; and these parts, he further shewed, are organs which belong to man in common with the lowest creatures, their united function being to supply food, the first necessary want of all animals: he termed this set of nerves the "Original" class, and included in it the nerves of the various organs of the senses. The Second class comprises a series of nerves distinct from the former, both in their origin and mode of

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distribution; they pass off from a circumscribed central portion of the nervous system, the medulla oblongata, and diverge to different parts of the head, neck, throat, and chest, already supplied by the original class: he shewed that these structures form together a mechanism for respiration, not found in the lowest animals, but gradually introduced by a slow process of development into the animal kingdom, in order that, besides oxygenating the blood, it may be, in Man, the organ of Voice and Expression: to this set of nerves he applied the name, 'Respiratory" class. In these two classes are combined all the nerves together which arise either from the Brain or Spinal Marrow. The Third class consists of a series of nerves which have their centre in large ganglions, scattered principally among the viscera of the abdomen; this forms the system called ganglionic or "Sympathetic :" and their use has been generally supposed to be, to unite in sympathy those organs by which the various organic functions are performed: such as secretion, absorption, assimilation of the food, the growth and decay of the body, &c. When the nerves belonging to these different classes are viewed, as by the anatomist, in their combined condition, crossing, joining, and interlacing, in the different parts of the body, nothing can exceed their apparent confusion; but when examined by the aid of the principle, and the arrangement, introduced by Sir Charles Bell, order and design are found to pervade every part.