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vered; yet, as we observe this more is imperfect, consisting generally of or less developed, in the higher class- but one ventricle, or is wanting. es of animals, according to the sta- The blood, or more properly sanies, tion occupied by the species, we might is cold, limpid, and colorless. These almost venture to infer from analogy are insects, worms, moluscæ, zoothe existence of nerves in those low- phytes, animalculæ, &c. This group est of animals, where their extreme comprehends, as we may see, many minuteness may render it impossible classes of animals, differing widely to trace them by the dissecting knife, from each other in structure and conor ascertain their existence by the formation,-yet all agreeing in certain microscope ;-or rather, perhaps, may particulars, and distinguished from we not admit, (and it seems probable,) the other groups, rather by what they that sensation, or a nervous power, want, than by what they possess, in very defined, it is true, resides or is common. Among those exhibiting diffused in such animals, (we allude the rudiments of a heart, its forms to the zoophytes and others,) through- are very varied and different ;—many, out the whole mass and texture of and especially the extensive class of their composition, thus rendering worms, (vermes,) have no vestiges of them, as it were, structures of ner- this organ, their imperfect circulation vous matter?-Be this, however, as it being carried on by means of contracmay, plants have no nerves, and are tile tubes or vessels only. altogether unendowed with sensation. Unconscious, consequently, of their own existence, or of the existence of surrounding objects, they rise and flourish, and pass away, affording food to a multitude of animals, and man,gratifying his senses by their beauty or perfume, adding to the comforts and luxuries of civilized life, and constituting the rich charm and loveliness of the landscape of the world.

The tribes of animals which give life and spirit to this landscape, and which are so numerous, and so varied in habits and kinds, are divided into two large groups or general families, namely, the vertebral, (or those possessing a vertebral column,) and the invertebral, (or those not possessing a vertebral column).-The group of vertebral animals is subdivided, First, into those whose skeleton is perfect; the heart consisting of two auricles, and two ventricles,-the blood warm and red. These are man, mammalia (that is, all animals that suckle their young), and birds. Secondly, into those whose skeleton is less perfect; -the heart consisting of one auricle, generally, and one ventricle ;-the blood cold and red. These are amphibious animals, reptiles, and fishes.

The group of invertebral animals have no internal skeleton ;-the heart

In all animals, a certain process, termed respiration, is requisite for the preservation of life;-this, in the mammalia and birds, and most of the amphibia, consists in drawing into the lungs a certain quantity of atmospheric air, the oxygen of which acting upon the blood, deprives it of a portion of the carbon it contained, and renders it fit for the purposes of the animal economy.-The tribe of fishes inhabiting the water, have organs termed gills, adapted for respiring the fluid in which they live, and by the agency of which the necessary change in the blood is effected.-Insects and worms, unfurnished with lungs, or gills, have spiracles for breathing in a peculiar manner, extended over various parts of their bodies, by means of which the oxygen of the atmospheric air is enabled to come in contact with the blood or sanies, and effect that peculiar change in it, which the economy of these animals may require.

Having thus endeavored to render clear and distinct the boundaries which nature has established, as separating organic and inorganic bodies,-and fixed a line of division between the animal and vegetable kingdoms,—we may proceed with advantage to consider the powers, which, inherent in the living body, enable it to preserve

its organic existence. These are sensibility and contractility, to which may be added instinct.

The animal frame is composed of solids and fluids. The solid parts, in the more perfect animals, are,

1st. The bones,-hard unbending fulcra, giving support and determinate figure to the body, and serving as levers, upon which the moving powers of the body act.

2d. The muscles,—the moving powers, or active instruments of motion. The texture of each muscle consists of a multitude of fibres,-divisible to an infinite degree,-running parallel to each other; the whole being surrounded by a delicate membrane, or fascia. Under a broad survey, we may divide them into the voluntary, or those obedient to volition, and the involuntary, or those not under the control of the will;-but we must not forget that some of the involuntary muscles, as those of respiration, (which perhaps rather claim a middle place,) are so far obedient to the will, as to be accelerated, diminished, or for a time suspended, in their action, at pleasure; although, in their natural state, their action, as much so as that of the heart, is perfectly involuntary.

3d. The nerves, or organs by which the frame is endowed with sensation. These are fibrous in their texture, white, and firm to the feel, but ramifying to a minuteness beyond conception. In man, nine pairs of nerves are found taking their origin from different parts of the brain, and supplying the nose, the eye, and muscles of the eyeball, the ear, and the tongue. The first, spreading on the membrane that lines the nose, is so constituted as to be affected by the volatilized particles of odorous bodies, while, the sensation being transmitted to the brain, we are thus endowed with the sense of smell. The second pair, expanding into what is termed the retina of the eyes, receives impressions through the medium of the rays of light, and thus we become acquainted with the forms and colors of external objects. The third and fourth, the

principal branches of the fifth, and the sixth pairs, are distributed among the delicate muscles placed at the back of the eyeball, and by which it is moved. The seventh divides into two branches, one of which (portio dura) ramifies on the face; but the other, soft and frail, (portio mollis,) and destined for receiving impressions from the vibrations of the air, is distributed in the internal parts of the ear, and affords to us the sense of hearing ;-by this nerve we receive all our pleasure from the harmony of music, or hang upon the charined breath of the speaker. The eighth and ninth pairs diffuse their branches on the tongue, and through them we are acquainted with the flavor of various substances; and to the ideas communicated by the impressions which they receive, we give the name of taste.

From the spinal cord, thirty-one pairs of nerves arise, distributed universally over every part of the body, communicating abundantly with each other, and forming, at various parts of their juncture, knots, or ganglia, the uses of which are not satisfactorily explained. These are the nerves on which depends general sensation, as well as those powers of the animal frame by which the existence and vigor of the whole is preserved.

4th. The bloodvessels: these are the arteries, conveying the blood from the heart to every part of the frame, to increase or repair it,—and the veins, which return the blood again to the heart, whence it passes immediately through the lungs, where it acquires properties fitted for its use in the system; from the lungs, it returns immediately back to the heart, and thence, in its now renovated state, it is poured through the aorta into all the arteries of the body, to be again returned by the veins as before.

5th. The absorbents: tubes adapted to supply, by means of nutriment, the loss or waste in the blood. There are two sets,-the absorbents, and, as they are commonly termed, the lacteals, (from lac, milk,) alluding to the milky fluid they contain.

6th. The exhalants: vessels or tubes for throwing off, as by perspiration, various excretions of the system.

7th. The membranous portions of the frame and the skin.

The fluid, necessary to life, and from which every other is secreted, (or separated,) as well as all solid parts of the frame, is the blood, composed of serum, fibrin, and coloring matter, which is conveyed, as we have mentioned, through every part of the body; and, by the agency of the extreme arteries, or capillary vessels, builds up this curious fabric, and repairs its losses. In the human body, the fluids have been estimated to bear a proportion of five-sixths to the whole; so that when these shall have evaporated, what remains? A little earth, and a mouldering skeleton. truth might the poet say—

With

"A little dust alone remains of thee, "Tis all thou art, and all the proud shall be."

Thus have we given a condensed sketch, in limine, of the composition of the organic animal frame, and now let us advance to a cautious examination of the powers by which it is enabled to maintain, and, to a definite period, continue its organic existence; -these we have already stated to be sensibility and contractility—to which we may add instinct.

By sensibility, is to be understood that faculty, peculiar to organic beings, and which, possessed by living organs only, renders them capable of receiving from appropriate agents, or stimuli, an impression which, stronger or weaker, alters, increases, or directs their respective functions.-These stimuli may be classed as external, by which we mean light, caloric, air, and various bodies,-or internal, by which we would imply volition, the passions or affections of the mind, and instinct. By contractility, is to be understood that power, by which each organ, having received an appropriate impression, or, in other terms, the sensibility of which is affected, is enabled to call itself into exertion, and execute its office.

Sensibility is either latent or percipient. By latent sensibility is indicated that modification which some organs possess, and which enables them to receive a natural impression, and to act, in consequence of it, without transmitting that impression to the brain ;-by percipient, that modification, by which an organ is enabled to transmit to the brain, as well as receive, the impression for which it may be adapted.

Contractility is either voluntary, and perceived, or involuntary, and unperceived.

These are the two essential properties connected with organic bodies, and on which all the phenomena they exhibit appear to depend ;-they ever accompany and coöperate with each other, and, except in abstract reasoning, are not to be separated ;— hence, we often hear them spoken of, by physiological writers, under the common term irritability, as including each.

In plants, and the polypi which in many respects resemble them, the sensibility is latent, and the contractility is involuntary and unperceived. For instance; the capillary vessels of a plant obeying the stimulus of the sap, which is circulated in them, contract and propel it through the whole system. Hence, too, delighting as it were in the warmth of the solar rays, the flowers and leaves of many plants, as the sunflower, turn to meet the rising orb, and follow him in his daily course; and hence the sensitive plant contracts on being touched. Now, we are not to suppose that the plant or its vessels have any consciousness of the presence of the sap, or of the general warmth of the sun;-no: it is true that the involuntary motions of plants do indeed depend upon sensibility, (latent,) but, possessing neither brain nor nervous system, they are in themselves unconscious of every action they perform;-for feeling, or a sentient power, (percipient sensibility,) is only found in animals possessing a brain and nervous system; and the more perfect these organs, the more perfect is sen

sation. The polypus, constituted without brain or nerves, and endowed only with the same latent sensibility, may contract or expand, but it cannot be said to enjoy the power of perception. In man, and the higher orders of animals, whose brain and nervous system are completely developed, the percipient powers (or the power of percipient sensibility) are in full per fection; and by these powers we are united to surrounding objects, the brain being the centre to which every impression is referred. But we must observe, that in the higher orders of animals, and man, a complete percipient power is only possessed by particular organs, each in its own degree and modification,-while all those by which nutrition and the circulation are effected, are endued with latent sensibility.

The heart, for instance, contracts in obedience to the stimulus which the blood communicates, but of the presence of this fluid we ourselves feel unconscious, nor do we perceive, in health, the usual and natural contractions of the heart, much less of the multitude of smaller vessels pervading every part of the system. Thus the animal frame in this light may be viewed as a compound machine, con

sisting of two sets of organs,—one set, by which we become conscious of external objects, and of our own existence; by which the actions of the will are performed, and which administer to our convenience or pleasure ;—the other destined for the internal or organic life, and preservation of the body. The former comprehends the organs of the senses, as they are termed, and the agents of voluntary motion;-the latter, the organs of digestion, circulation, and secretion. By experience and research only, do we know of the existence of these organic operations; and their actions, of which we are unconscious, manifest themselves but by their effects. And here may we not pause to admire the wisdom of the Divine Architect! How well is all this ordered ! For did we perceive the multitudinous workings of this organic machine,—were the contractions and labors of every tube, the beatings of every "petty artery," cognizable by our senses, in what a state should we pass through life!How little could we perform of our respective duties !-How would every trifling variation, every change, affright us -But it is not so! Surely this is not by chance; "in wisdom hath He made them all."

THE MESSAGE TO THE DEAD.

BY MRS. HEMANS.

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'Messages from the Living to the Dead are not uncommon in the Highlands. The Gael have such a ceaseless consciousness of Immortality, that their departed friends are considered as merely absent for a time; and permitted to relieve the hours of separation by occasional intercourse with the objects of their earliest affection."

THOU'RT passing hence, my brother! Oh! my earliest friend, farewell! Thou'rt leaving me without thy voice, In a lonely home to dwell; And from the hills, and from the hearth, And from the household tree, With thee departs the lingering mirth, The brightness goes with thee.

See the Notes to Mrs. Brunton's " Discipline."

But thou, my friend, my brother! Thou'rt speeding to the shore Where the dirge-like tone of parting words, Shall smite the soul no more!

And thou wilt see our holy dead,

The lost on earth and main ! Into the sheaf of kindred hearts Thou wilt be bound again!

Tell thou our friend of boyhood,
That yet his name is heard

On the blue mountains, whence his youth
Pass'd like a swift bright bird.
The light of his exulting brow,
The vision of his glee,

Are on me still-oh! still I trust
That smile again to see.

And tell our fair young sister, The rose cut down in spring, That yet my gushing soul is fill'd With lays she loved to sing.

Her soft deep eyes look through my dreams,
Tender and sadly sweet;

Tell her my heart within me burns
Once more that gaze to meet !

And tell our white-hair'd father,
That in the paths he trode,
The child he loved, the last on earth,
Yet walks and worships God.

Say, that his last fond blessing yet

Rests on my soul like dew, And by its hallowing might I trust Once more his face to view.

And tell our gentle mother, That o'er her grave I pour The sorrows of my spirit forth, As on her breast of yore! Happy thou art, that soon, how soon! Our good and bright will see; Oh! brother, brother! may I dwell Ere long with them and thee!

MUCKLE-MOU'D MEG AND THE LANG GUN.

A REMINISCENCE OF A FOWLER.

THERE had been from time immemorial, it was understood, in the Manse, a duck-gun of very great length, and a musket that, according to an old tradition, had been out both in the Seventeen and Forty-five. There were ten boys of us, and we succeeded by rotation to gun or musket, each boy retaining possession for a single day only; but then the shooting season continued all the year. They must have been of admirable materials and workmanship; for neither of them so much as once burst during the Seven Years' War. The musket, who, we have of ten since thought, must surely rather have been a blunderbuss in disguise, was a perfect devil for kicking when she received her discharge; so much so indeed, that it was reckoned creditable for the smaller boys not to be knocked down by the recoil. She had a very wide mouth-and was thought by us "an awfu' scatterer;" a qualification which we considered of the very highest merit. She carried any thing we chose to put into her there still being of all her performances a loud and favorable report balls, buttons, chucky stanes, slugs, or hail.

She had but two faults-she had got addicted, probably in early life, to one habit of burning priming, and to another of hanging fire; habits of which it was impossible, for us at least, to break her by the most assiduous hammering of many a new series of flints; but such was the high place she justly occupied in the affec

15 ATHENEUM, VOL. 1, 3d series.

tion and admiration of us all, that faults like these did not in the least detract from her general character. Our delight when she did absolutely and positively and bonâ fide go off, was in proportion to the comparative rarity of that occurrence; and as to hanging fire-why we used to let her take her own time, contriving to keep her at the level as long as our strength sufficed, eyes shut perhaps, teeth clenched, face girning, and head slightly averted over the right shoulder, till Muckle-mou'd Meg, who took things leisurely, went off at last with an explosion like the blowing up of a rock.

The "Lang Gun," again, was of a much gentler disposition, and, instead of kicking, ran into the opposite extreme on being let off, inclining forwards as if she would follow the shot. We believe, however, this apparent peculiarity arose from her extreme length, which rendered it difficult for us to hold her horizontally-and hence the muzzle being attracted earthward, the entire gun appeared to leave the shoulder of the Shooter. That such is the true theory of the phenomenon seems to be proved by this-that when the " Lang Gun" was, in the act of firing, laid across the shoulders of two boys standing about a yard the one before the other, she kicked every bit as well as the blunderbuss. Her lock was of a very peculiar construction. It was so contrived that, when on full cock, the dog-head, as we used to call it, stood back at least seven

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