Abbildungen der Seite
PDF
EPUB

217

Orang Outang of Sumatra.

248

sensibility, that he ordered the process of | tion, might as obviously increase his length skinning to stop till the head had been to 8 feet.ol

removed.

It seems probable that this animal had travelled from some distance to the place where he was found, as his legs were covered with mud up to the knees, and he was considered as great a prodigy by the natives as by the Europeans. They had never before met with an animal like him, although they lived within two days' journey of one of the vast and almost impenetrable forests of Sumatra. They seemed to think that his appearance accounted for many strange noises, resembling screams and shouts, and various sounds, which they could neither attribute to the roar of the tiger, nor to the voice of any other beast with which they were familiar. What capability the great orang outang may possess of uttering such sounds does not appear, but this belief of the Malays may lead to the capture of other individuals of his species, and to the discovery of more interesting particulars of his conformation and habits.

The only material discrepancy which I can detect in the different accounts which have been given of this animal, regards his height, which in some of them is vaguely stated at from above six feet to nearly eight. Captain Cornfoot however, who favoured me with a verbal description of the animal when brought on board his ship, stated, that "he was a full head taller than any man on board, measuring seven feet in what might be called his ordinary standing posture, and eight feet when suspended for the purpose of being skinned."

The following measurements, which I have carefully made of different parts of the animal in the Society's Museum, go far to determine this point, and are entirely in favour of Captain Cornfoot's accuracy. The skin of the body of the animal, dried and shrivelled as it is, measures in a straight line from the top of the shoulder to the part where the ancle has been removed, 5 feet 10 inches, the perpendicular length of the neck as it is in the preparation 3 inches, the length of the head from the top of the forehead to the end of the chin 9 inches, and the length of the skin still attached to the foot from its line of separation from the leg 8 inches: we thus obtain 7 feet 6 inches as the approximate height of the animal. The natural bending posture of the ape tribe would obviously diminish the height of the standing posture in the living animal, and probably reduce it to Captain Cornfoot's measurement of 7 feet, whilst the stretching that would take place when the animal was extended for dissec

Description of the remains of the animal-Head. The face of this animal, with the exception of the beard, is nearly bare, a few straggling short downy hairs being alone scattered over it, and is of a dark lead colour. The eyes are small in relation to those of man, and are about an inch apart: the eyelids are well fringed with lashes. The ears are one inch and a half in length, and barely an inch in breadth, are closely applied to the head, and resemble those of man, with the exception of wanting the lower lobe. The nose is scarcely raised above the level of the face, and is chiefly distinguished by two nostrils three-fourths of an inch in breadth, placed obliquely side by side. The mouth projects considerably in a mammillary form, and its opening is very large; when closed, the lips appear narrow, but are in reality half an inch in thickness. The hair of the head is of a reddish brown, grows from behind forwards, and is five inches in length. The beard is handsome, and appears to have been curly in the animal's life-time, and approaches to a chesnut colour; it is about three inches long, springing very gracefully from the upper lip near the angles of the mouth, in the form of mustachios, whence descending, it mixes with that of the chin, the whole having at present a very wavy aspect. The face of the animal is much wrinkled. bu? )

Hands. The palms of the hands are very long, are quite naked from the wrists, and are of the colour of the face. Their backs, to the last joint of their fingers, are covered with hair, which inclines a little backwards towards the wrists, and then turns directly upwards. All the fingers have nails, which are strong, convex, and of a black colour; the thumb reaches to the first joint of the fore-finger.

Feet. The feet are covered on the back with long brown hair to the last joint of the toes; the great toe is set on nearly at right angles to the foot, and is relatively very short. The original colour of the palms of the hands and the soles of the feet is somewhat uncertain, in consequence of the effect of the spirit in which they have been preserved.

1

[blocks in formation]
[ocr errors]

hangs shaggy below the arm; from the shoulders it hangs in large and long massy tufts, which incontinuation with the long hair of the back, seems to form one long mass to the very centre of the body. About the flanks the hair is equally long, and in the living animal must have descended below the thighs and nates. On the limits, however, of the lateral termination of the skin which must have covered the chest and belly, it is scanty, and gives the impression that these parts must have been comparatively bare. Round the upper part of the back it is also much thinner than elsewhere, and small tufts at the junction of the skin with the neck are curled abruptly upwards, corresponding with the direction of the hair at the back of the head. orobrego9 49 (99%,

[ocr errors][merged small]

system, for its support and nourishment, so it is the office of the veins to return it to the same source, its important task being accomplished. All the veins of the body, except those of the heart itself, terminate ultimately in the two vena cave, from whence the blood passes into the right auricle; this reservoir being filled, its sides immediately contract, and the blood is forced through the ostium venosum into the right ventricle, being prevented from returning back into the veins by the valve placed at their entrance into the auricle. The right ventricle, on receiving the blood, now in its turn contracts, and forces it into the pulmonary artery, by which it is carried immediately to the lungs, where, undergoing certain changes, it becomes fitted for the purposes of the animal economy. On the contraction of the ventricle it would be natural to expect that the blood would, at least in part, return back into the auricle, and this would cer tainly occur, were it not prevented by the valve at the ostium venosum, or entrance into the ventricle; the same remark holds good, with respect to the valves also on the other side of the heart.

[ocr errors]

The blood having traversed the lungs, is returned by the pulmonary veins to the left auricle of the heart; and this contracting, it is propelled into the left ventricle, from whence it is sent through the aorta and its ramifications to every part of the body; and is again returned by the veins to the right auricle. It appears, therefore, that the blood on the right side of the heart, must pass through the lungs, before it can be admitted into the left, in order to be conveyed by the means of arteries through the system.

FROM the left ventricle of the heart, as we have before stated, the main artery of the frame, termed aorta, arises; this vessel distributes its branches, like a tree, to every part of the body, forming, as they proceed, numerous communications with each other, till at last, by their extreme ramifications, termed capillaries, a network of such deli cacy and minuteness is produced, that a puncture with the finest instrument cannot be made without wounding them, and drawing blood. The capillaries gradually assume the character of veins, as minute and delicate as themselves, assisting equally to form the network, and so intimate is their union; and so imperceptibly do the veins assume their venous character, that it would be difficult to say, where the artery ends, and the vein begins. This beautiful system of minute vessels is distributed throughout every part of the body but the skin; the various membranes, and the muscles, are supplied the most abundantly. It is not, however, into all the capillary vessels, in a natural state, that the red particles of the blooding, it may be proper to give a brief deare admitted as for instance the cornea of the eye, whose vessels contain the serous, or uncoloured, portion only. This may arise from the calibre of the vessels being too mi nute to admit the entrance of the red parti cles, or, from a natural disposition and pow er in them, to refuse that part of the blood which would interfere with the necessary function of the organ.

As it is the office of the arteries to convey the blood from the heart to every part of the

111.-VOL. X.

Now, we shall find, upon examination, that a manifest difference exists between the blood in the veins, and in the arteries, or, in the right, and in the left cavities of the heart; that of the veins of the right side of the heart being of a dark livid colour, while its hue in the arteries and left side is scarlet or bright red. This circumstance, independent of others, indicates a change in its nature, and it is evident also, that this change must be effected in the lungs. But before proceed

scription of these organs, by which some idea of their structure and use may be formed.

The lungs are situated in the cavity of the chest, which when distended with air, they completely fill; their texture, is light and spongy, and consists of an assemblage of most minute and numberless cells, connected together and communicating with each other; the whole being covered by an extremely fine membrane termed the plura. In these cells the ramifications of the tra

R

251

Essays on Physiology: Essay V.

chéa or wind-pipe terminate, and it is in these that the blood undergoes its change. The lungs are abundantly supplied with absorbents, and also with a considerable number of nerves, although at the same time their sensibility is very imperfect. On

each dilatation of the chest there enters into these organs, according to some physiologists, between thirty and forty cubic inches, or, at a deep inspiration, from six to eight quarts of atmospheric air, consisting when pure, of 73 of azote or nitrogen, 27 of oxygen, and one or two parts in the 100, of carbonic acid: the character of the air, when expired, is found to be considerably altered, the portion of carbonic acid being much increased, that of the oxygen diminished, and the azote remaining apparently unchanged.

Now, on the air-cells of the lungs, the contexture of which is estimated by Hâller at the 1000th part of an inch in thickness, the extreme ramifications or capillaries of the pulmonary artery are spread like a delicate network; and under such circumstan. ces it appears, that the oxygen of the atmosphere is fully capable of acting on the blood, and affecting the requisite changes, by which, having become arterial, it is returned through the pulmonary veins, to the left side of the heart. We may here remark, that the pulmonary artery is the only artery which carries dark, or, as it is commonly called, venous blood, and it arises from one of the right cavities of the heart; while the pulmonary veins proceeding to the left are the only veins that carry arterial blood thus the blood in the right cavities of the heart is dark-coloured, or venous; that in the left, bright red, or arterial.

With the passage of this fluid through the lungs is connected that most important phenomenon, the nourishment and support of the body. It is remarkable that arterial blood seems to be alone calculated to sustain the natural integrity of the animal frame; its decay and losses being repaired, and its various secretions being furnished, from arterial blood. To this rule there is however one exception, viz. the bile; this fluid is secreted by the liver from venous blood.

In venous blood is contained a large portion of carbon, acquired during its course through the animal system. Now, when it reaches the lungs, and becomes acted upon by the atmospheric air, which I have already said to be comprised principally of oxygen and azote, the oxygen unites with a great portion of the carbon, forming carbonic acid, expired with the azote, which seems to be unchanged, and also with the remainder of the oxygen which exists after the production of the acid. The blood now

[ocr errors]

252

becomes of a florid colour, having parted with the carbon, to which its previous darkness was owing; and this is supposed to be the only change it undergoes during respiration. It has been, however, the opinion of several physiologists, that a part of the oxygen was absorbed by the blood, and so entered into combination with it. This again is contradicted, and with reason, as it is ascertained by experiments that the portion of oxygen which disappears, is just sufficient for the formation of the carbonic acid which is produced.

*u

The quantity of oxygen consumed by animals in a given time is variable, not only as it regards species and individuals, but the same individual under different circumstances.

[ocr errors]

In man, the quantity of oxygen consumed in a minute has been differently rated. Allen and Pepys found it to be 26'6 cubic inches in a minute; Davy 31-6; and Murray 36. Various states of the system, however, occasion considerable differences. For instance, the quantity of oxygen consumed, is increased by exercise; and if the experiments of Peguin may be trusted, this consumption is nearly four times more than in the usual state of the body. But Prout, who has paid much attention to the subject, concluded from numberless experiments, that exercise, when moderate, increased the consumption of oxygen, but when continued so as to induce fatigue, diminished it. The exhilarating passions, appear to increase the quantity, the depressing passions on the other hand, and sleep, alcohol, and tea, to diminish the quantity. The experiments of Dr. Prout tend also to prove, that the quantity of oxygen consumed, is not uniform during the twenty-four hours, but is always greater at one and the same part of the day than at any other. For instance, that its maximum occurs between 10 a. m. and 2 p. m., or generally between 11 a. m. and 1 p. m, and that its minimum commences about 8h. 30′p. m., and continues nearly uniform till about 3h. 30' a. m.

To account for this phenomenon, Dr. P. refers, and with much probability, to the sun, as regulating by its presence or absence these variations. And we may here observe that in all diurnal animals, the season of their greatest activity is the forenoon, at which time also the consumption of the oxygen is greatest, while lassitude and fatigue come on gradually in the afternoon, when the consumption of oxygen is diminished. There are, however, many animals from whose natural habits of activity in the night, and repose during the day, we may conclude that with them the arrangement is reversed.

From the experiments of Dr. Crawford, it would appear, that temperature exerts much influence also, as to the quantity of oxygen consumed. He found, for example, that a guinea-pig confined in air at the temperature of 55°, consumed double the quantity which it did when confined in air at 104°; and also that in such cases of exposure to high temperature, the venous blood had not its usual dark character, but, by its arterial florid hue, indicated that in its course through the system, the natural and usual changes in it had not taken place.

When the temperature of warm-blooded animals is greatly increased, exertion becomes laborious, and fatigue and lassitude, as if resulting from violent muscular efforts, are speedily induced; but on the contrary, in cold-blooded animals, on whose system temperature has so marked an influence, that when cooled below a certain degree they become torpid, the effect of a moderate degree of heat will be to increase muscular action, and a corresponding consumption of oxygen. As then it appears that an increase of muscular action (to a certain point at least) is accompanied by an increased consumption of oxygen; so, on the other hand, as fatigue follows exertion, this increased consumption will always be succeeded by an equally great decrease, and this is indicated by yawning and drowsiness, which are also the signs of muscular exhaustion. The amount of oxygen consumed is an index of the quantity of carbon thrown out of the system, and this in man amounts to nearly half an ounce every hour, but its relative proportion to the quantity of food taken into the system, or to the bulk or natural habits of the animal, is yet undetermined by experiments.

The blood having thus become aerated, or, to speak more correctly, deprived of the carbon which it had acquired in its course through the frame, is now fitted for the purposes of the animal economy; and it is in the order of our plan to take a closer view of the agents appointed to this end. Our readers need not now be told that these are the heart, the arteries, and the veins. The general anatomy of the heart has already been explained; it now remains for us to consider its peculiar mode of action.

We have stated this organ to be a muscle, containing four cavities, destined for receiving and expelling the blood; but with respect to its action, it differs from every other in the animal frame. To other muscles, rest from their labours is necessary, that their powers, of exertion may be renewed; they are wearied with toil, and require repose; those even by which respiration is effected,

are refreshed at each interval; but the heart alone is unwearied, it continues its labour for years; it requires no repose; death alone puts a period to its exertions; and even then life lingers there the latest, and slowly and unwillingly retires. The heart, we have said to consist of two auricles and two ventricles, and their contraction separately on the blood has been mentioned, but it must not be thence concluded, that each of these divisions in turn contracts separately and by itself, no other action of the heart occurring at the same time; for this is by no means the case. The two auricles contract and dilate together, and it is the same with respect to the ventricles, whose motions are simultaneous also; the contraction of one part, and the dilatation of the other, both occurring at the same period. It may be observed here, that when the contraction of the heart is mentioned in general terms, that of the ventricles is always alluded to.

On each action of the ventricles, the whole of the heart is carried smartly forwards, and the point of this organ comes in contact with the left side of the chest, between the sixth and seventh true ribs, when its pulsation may be easily felt. From this circumstance, a controversy has arisen among physiolo gists, respecting the mode in which the contraction takes place; some supposing the heart at that instant to be elongated; and others, with better reason, affirming it to be shortened; and numerous were the animals sacrificed, to prove the truth of each assertion. The question is now set at rest, as it is ascertained that the external portion of the ventricles is drawn towards the septum or partition between them, and the apex or point towards the base; the displacement of the heart being therefore to be attributed to the influx of blood into the auricles, and to its expulsion from the ventricles, by which the aorta and pulmonary artery are distended. The pulsations of the heart during health vary much, according to the sex, habits, or temperament of the individual; their frequency, however, decreasing from infancy to old age.

I

In the new-born infant, the pulse may be estimated at 140 per minute; at the end of the first year 124-second 110-third and fourth 96;-in youth from 80 to 86-manhood 75-old age 60. But as life advances farther, the pulse is found so, variable, that no accurate estimate can be taken.

The heart, through the medium of the nerves, is greatly influenced by the passions and affections of the mind; its action is modified and often accelerated by the slightest emotion; and diseases of every kind

255

Measures taken for the Abolition of Slavery in Ceylon.

control, diminish, and even excite its powers; and by this derangement other parts of the system are again influenced; for the animal frame may be said to resemble a piece of mechanism, furnished with numerous wheels depending on and giving aid to each other; but let one be displaced or put out of order, the whole is thrown into confusion. Fainting, for instance, we know is often occasioned by emotions of the mind, by which, through the medium of the nerves, the action of the heart is diminished, and less blood is consequently sent through the vessels to the brain. Now, from this deficiency, the nervous power of the brain becomes diminished, or even for a time suspended, as it depends materially on the circulation, and the body sinks inanimate; nor perhaps would it recover, had not the heart the property of still preserving its power of contraction to a certain degree, which, as the blood begins again to circulate slowly through the brain, it more and more recovers; and as it recovers, sends forth by degrees a still greater portion of blood, till at last the whole circulation becomes fully restored. Hence we see the reason why persons fainting should be placed in a horizontal position, with the head as low or lower than the rest of the body.

The arteries, we have before stated, may be considered as ramifications of one great trunk; they are composed of three coats, the external one consisting merely of cellu. lar membrane, the middle one of fibres encircling the artery, and asserted by many to be muscular; and the internal one, a thin membrane calculated to give strength to the artery, and afford at the same time, by the smoothness of its surface, a free and easy passage to the blood. The veins also in like manner are composed of three coats; but as their structure is much more delicate than that of arteries, it is a difficult matter to demonstrate the fact, while, on the contrary, the coats of arteries from their structure easily admit of separation. The arteries and veins are both elastic, and capable of dilation to a considerable degree, but the latter possess this power more remarkably than the former, and it is indeed astonishing to how great an extent this may be carried without injury. Hammersmith.

W. MARTIN.

(To be continued.)

MEASURES TAKEN FOR THE ABOLITION OF
SLAVERY IN CEYLON.

THE name of Sir Alexander Johnston will
be long remembered in India, where his
impartial administration of justice, and

256

humane endeavours to ameliorate the condition of the natives, have been attended with the most happy effects. The following letter, written by this gentleman, on the measures adopted for the abolition of slavery in Ceylon, dated July 22d, 1816, will place his character, exertions, and success, in an amiable light.

"I have, for the last ten years of my residence in Ceylon, been endeavouring, as I believe I have often mentioned to you, to get the principal proprietors of slaves on the island to fix a day, after which all children born of their slaves shall be considered as free. My endeavours have, at last, as you will see by the enclosed papers, been attended with success. I wrote on the 10th of this month, a letter (of which No. I.* is a copy,) upon the subject, to the principal proprietors of slaves at this place, who are upon the list of the special jurymen for the province of Colombo, and who are therefore all personally known to me. By the letter, of which No. II. is a copy, you will see that the proposal contained in my letter was well received by them; and that they, at a general meeting which they called to take the contents of that letter into consideration, unanimously came to the resolution, that all children born of their slaves, after the 12th of August next, should be free;-(the 12th of August was fixed upon by them, at my suggestion, as a compliment to the Prince Regent.) They afterwards appointed a committee, from among themselves, to frame certain resolutions, (No. III.) for the purpose of carrying their benevolent intention into effect. The principal object of these resolutions is, as you will perceive, to secure that the children, born free after the 12th of August next, shall be provided for by the masters of their parents until the age of fourteen; it being supposed that after they have attained that age they will be able to provide for themselves.

"The Dutch special jurymen of this place consist of about 130 of the most respectable Dutch gentlemen of the place; in which number are contained almost all the Dutch who are large proprietors of slaves. Besides these gentlemen, there are jurymen of all the different castes among the natives, such as vellales, fishermen, men of the Mahabadde or cinnamon department, Chittees, and Mahomedans. The moment the jurymen of these castes heard of the

In the Eleventh Report of the " African Insti tution," from which this extract is taken, the let ters here marked No. I. II. III. &e, are inserted, but we are obliged to omit them from the want of

room.

« ZurückWeiter »