7. The second plate represents a back view of the male skeleton, while the first is a front view.

a. The parietal bone.

b. The occipital bone.

c. The temporal bone.
d. The cheek bone.

e. The lower jaw bone.

Neck and Trunk.

a. The bones of the neck. b. The bones of the back. c. The bones of the loins. d. The hip bones.

e. The sacrum.

Upper Extremity.

a. The collar bones.

b. The blade bone.

c. The upper bone of the arm.

d. The radius.

e. The ulna.

f. The bones of the wrist.

g. The bones of the hands.

h. The first row of finger bones.

i. The second row of finger bones.

k. The bones of the thumb.

Lower Extremity.

a. The thigh bone.

b. The large bone of the leg.
c. The small bone of the leg.

d. The heel bone.

e. The bones of the instep.
f. The bones of the toes.

8. It does not fall within the plan of the present work to give a description of the individual bones which go to make up the skeleton; this must be sought in treatises on anatomy. Still there are many points connected with the subject of extreme interest to every reflecting mind, to which the attention of the young may be profitably directed, particularly as connected with the marks of wisdom and design in the Almighty architect. If our curiosity is excited to see a piece of ingenious machinery, or a new engine, shall we neglect to raise the covering which displays in the body the most striking proofs of design, surpassing all art in simplicity and effectiveness, and without any thing useless or superfluous.

9. If we compare the human body, as a work of art, with any forms of human architecture, how vastly superior does it appear. A watch, or a musical automaton are highly ingenious specimens of inventive skill; but where is the watch or the automaton that can, without repair, for the space of 80 or 100 years, continue to perform its movements with regularity and precision. And yet how much less complicated is their machinery, how vastly more solid, and durable the materials out of which they are formed!

10. If we examine a ship, we find it built for passive motion, and for resisting force externally applied; a house or a bridge is constructed for solidity and firmness, on the principle of gravitation; a railroad car is built for rapid motion, and its wheels so adjusted, that they may not run off the track; but in the human body, we find not only securities against the gravitation of the parts, provisions to withstand shocks and injuries from without, but at the same time, the frame work is calculated to sustain an internal impulse from the muscular force which moves the bones as levers, or like a hydraulic engine, propels the fluids through the body.

11. The human fabric is admirably adapted to resist the influences to which it is subjected; in other words, there is a nice balance between the power of exertion and the capability of resistance. A deer or a giraffe is never injured by any leap which their muscular powers enable them to make, because the inert power of resisting the shock, bears a relation to the muscular power with which they spring; and so it is in man. The elasticity of his limbs is proportioned very accurately to his activity; he readily resists shocks and impulses upon the lower extremities, because they are adapted to this end; but if the same are applied to the upper, the bones are broken or displaced, because they are adapted rather for extensive and rapid motion, than for resisting violent shocks.

12. It has been truly remarked that the foundation of the Eddystone light-house, the perfection of human architecture

and ingenuity, is not formed on principles so correct, as those which have directed the arrangement of the bones of the feet; that the most perfect pillar is not adjusted with the accuracy of the hollow bones which support our weight; that the insertion of a ship's mast into the hull is a clumsy contrivance compared with the connexions of the human spine and pelvis; and that the tendons are composed in a manner supe rior to the improved chain cables of Bloxham.

13. As the head is the noblest part, and the brain the most essential organ of the animal system, let us first direct our attention to it. The brain is liable to injuries, not only by sharp bodies touching and entering it, but by a blow upon the head, which shall vibrate through it, without the instrument piercing the skull; and such a blow would more effectually destroy a man's senses, than even if a sword penetrated into its substance. It is obvious, that if the bony case were soft it would be easily pierced; if of a brittle nature, it would be easily cracked, and if very firm and solid, like metal, it would ring and vibrate, and thus communicate the concussion to the brain.

14. To obviate these dangers, we find the skull composed of two plates of bone, one external, which is fibrous and tough, and one internal, so dense and hard, that it is called by anatomists the glassy table Now, as the brain is liable. to be hurt both by sharp and blunt instruments, the inner table is hard and brittle, calculated to resist any thing penetrating; while the outer table is tough to give consistence, and stifle the vibration which would take place, if the whole texture were uniform. This may be illustrated by an example. If a soldier's head be covered with a steel helmet or cap, the blow of a sword, which does not penetrate, will yet bring him to the ground; but if it be lined with leather and covered with hair, the vibration is not transmitted to the brain, and the wearer escapes without injury.

a

a, the external, b, c, the internal table; the intermediate cellular texture, being soft and spongy, and conveying vessels and nerves from one part to another.

15. It is worthy of particular remark, how the changes. in the structure of the bones of the skull are adapted to the changes in the mind at different periods of life. (At birth, the skull is soft and yielding, there being considerable intervals between the adjacent bones of which it is composed; during childhood, it is highly elastic, so that the heedlessness of that period may not endanger concussion, to which it is so often exposed from falls; and during youth and up to manhood, the parts which are exposed to the contact of external bodies, are thicker, and the bones are still not firmly consolidated at their sutures or seams, by which they are united. As old age approaches, man grows more timid, and is little disposed to feats of agility or activity; something teaches him that falls or blows, which could once be borne with impunity, can no longer be encountered with safety; and if we examine the skull, we find the two layers of bone consolidated into one. The result of which is, that concussion at this period would be far more dangerous than in early life, or at the age of manhood.

16. The sutures, or joinings of the bones of the skull, in terrupts, in a measure, the shock of the vibration produced by external violence, and also prevent fractures from extending as far as they otherwise would do, in one continued bony substance, No one can examine the joinings of two of the bones of the cranium, without admiring the minute dovetailing by which one portion of the bone is inserted into, and surrounded by the other, whilst that other pushes its processes out between those of the first in the same manner;