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strument precisely because he is already superior to all other animals. And the converse is equally true, that, with intellectual powers of even a higher order than those which they already possess, human beings could not live in a state of society, could hardly indeed exist in any state, unless furnished with such an instrument as the hand.

SECTION II.

Differences in the Form of the Infant and of the Adult; particularly with reference to the Spine.

AND yet, notwithstanding the confessed superiority of man, if we view him only in the infancy of his individual existence, what is there that is calculated to give an earnest of his future vigour and activity, either with respect to bodily or mental powers; and what are all the advantages of the external world to a creature so utterly helpless, so utterly incapable of using or even passively enjoying them? In fact, with the exception of a very few instinctive rather than voluntary acts, such as that of deriving its nutriment from the mother's breast, the infant is, from the feebleness of its powers, incapable of efficient exertion; and depends entirely on the assistance of those around. it.

The physical differences, observable in comparing the structure of the infant with that of the adult, which enable the one to execute many operations of which the other is incapable, exist to a certain extent in every part of the body; but are perhaps more remarkable in the spine than in any other part: and the spine therefore may be selected as a fit term of comparison.

In considering the office of the adult spine, with a view to the present subject, we find that great strength, combined with great flexibility, is particularly requisite. With reference to strength, the pyramidal form of this natural column is obviously

conducive to the purpose intended; and the arrangement of the solid matter, of which it is composed, is such as to contribute to the same effect; for that solid matter, instead of being collected into one compact mass, is diffused in such a manner as to resemble the structure of sponge; and it is well known, with reference to the strength of artificial columns, that, the same quantity of matter being given for each, and their height being the same, those columns which are hollow are stronger than those which are solid. Again, the whole column is made up of numerous parts, called vertebræ, which are so firmly bound together as to lessen the chance of being broken in the act of bending; and these vertebræ being applied to each other, throughout, by broad horizontal surfaces, are thus best calculated to support the perpendicular pressure of the superincumbent parts. The effect of general strength is further accomplished by the mutual locking in of the projecting portions, or processes, of the several vertebræ; and the same effect is accomplished to an additional extent among these vertebræ which belong to the thorax or chest, by the mode of articulation between them and the ribs; each rib being united, not entirely to a single vertebra, but partially to two contiguous vertebræ, near their line of junction.

The flexibility of the spine is secured to the utmost requisite extent, by the great number of articulations or joints which it possesses, amounting to more than twenty; as well as by the elasticity of the substance constituting those joints: and the projecting parts or processes of the several vertebræ, which serve for the insertion of the muscles and tendons which are to move the whole, are differently disposed in the neck, the back, and the loins; so as to be accommodated to the degree and kind of motion required in each: thus the vertebræ of the neck admit of a lateral motion to a greater extent than those of the back; and the vertebræ of the back admit of flexion and extension to a greater degree than those of the neck;

while the vertebræ of the loins, being intended for support rather than flexibility, have their processes so distributed, as to contribute principally to the former of those effects.

Thus far we have considered the conditions of the adult spine, and have seen that they are calculated most admirably both for flexibility and for strength. Let us now examine the same column in the age of early infancy; and here we shall see, that, although at that period the parts, in which the conditions of strength and flexibility are so remarkably developed in the adult state, are not yet formed, or not completed; those parts which are essential to the security of the life of the individual are nearly in as perfect a state as at the age of manhood: so that in the midst of the most decided marks of weakness and imperfection in the rest of the column, there is an extraordinary instance of strength and perfect growth, in precisely that part of it which could not have been left in an incomplete state, without manifest, immediate, and constant danger to the individual. In other words, the bodies and processes of the several vertebræ on which the strength and flexibility of the spine depend, are in early infancy still in a soft or cartilaginous state; while the annular portions, which with their intervening ligaments constitute the spinal canal, are completely ossified; so as to give as great a degree of security to the spinal marrow as at the age of manhood.

Nor need we spend much time in ascertaining the final cause of this remarkable difference. Is it not indeed obvious on a moment's reflection, that the very helplessness and imperfect state of the physical powers in infancy, so ill understood and appreciated, though so beautifully described by Lucretius, contribute to the fuller developement of the moral character, not only of the individual, but of his parents also, and of all his immediate connexions. The mutual affection, for instance, that takes place and is cemented between the infant and its mother, during

the lengthened period in which the latter nurses her offspring; the stimulus, which is given to the exertions of the other parent in supplying the increasing wants of those who depend on him for support; and the general feeling and expression of good-will and attachment, which bind together the numerous individuals of the same family; all coincide to increase the sum of human happiness and virtue. Whereas, were the infant born with all its powers complete, and capable of exerting those powers as soon as born, independently of the assistance of parent, or sister, or brother; what would then remain of those endearing relations, but the empty name?

How incorrect then is the conclusion of the poet in that otherwise most beautiful passage of his poem! "The new-born babe, which, like the shipwrecked mariner, lies prostrate on the ground, naked and destitute of every assistance required for the support of life, pierces the surrounding air with its incessant cries; as if foreseeing the long train of miseries which it must hereafter encounter. And yet the tender foal and lamb not only begin to crop the grass, but play about the mother almost as soon as born. The nurse's soothing lullaby is not wanted by them, nor the excitement of the rattle or of any other toy: nor do they require a change of dress accommodated to the changing temperature of the surrounding atmosphere; nor arms for their defence, nor walled cities for their protection; kind nature supplying to them in bountiful profusion whatever is necessary to satisfy their wants."* As if it might not have been reasonably and safely concluded, that that same power, (call it "nature," or by any other name,) which provided so amply for the early wants of the lower species of animals, had some good and special reason for leaving the human infant in a temporary state of helpless weakness.

* Tum porro Puer, ut sævis projectus ab undis Navita, nudus humi jacet, infans, indigus omni

SECTION III.

Physical Superiority of Man, on what Principle to be estimated.

FROM this helplessness in his early years, and from the occasional inferiority of some of his physical organs to the corresponding organs of brutes, it has sometimes been absurdly asked what claim man has, from his physical structure or powers, to be placed first in the scale of animal beings. His strength, what is it to that of the elephant or of the horse, or even of some species of reptiles or fish? his powers of sight and motion, what are they to those of the bird? his sense of odours, to that of the dog? his touch, to that of the spider?

And yet, even if we entirely omit the consideration of the soul, that immaterial and immortal principle which is for a time united to his body, and view him only in his merely animal character, man is still the most excellent of animals. How confined are the powers of other animals, considered generally, when compared with those of the human species. The comb of the bee indeed is in its construction wonderful; and so is even the nest of the bird, or the habitation of the beaver: but these animals could never be taught to fabricate, or to use, the simplest of those machines or instruments, which man, even in a very partially civilized state, is in the daily habit of making

Vitali auxilio, cum primum in luminis oras
Nixibus ex alvo matris natura profudit;
Vagituque locum lugubri complet, ut æquum 'st
Cui tantum in vita restet transire malorum.

At variæ crescunt Pecudes, Armenta, Feræque;

Nec crepitacula eis opu' sunt, nec cuiquam adhibenda 'st
Almæ nutricis blanda atque infracta loquela:
Nec varias quærunt Vesteis pro tempore Cœli.
Denique non Armis opus est, non Manibus altis,
Queis sua tutentur, quando omnibus omnia large
Tellus ipsa parit, naturaque dædala rerum.
Lib. v. 223-235.

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