tary composition is that is to say, ferent states of the same individual. how many atoms of carbon, hydro- The blood of no two men is precisely gen, &c. are included in every 1000 similar; the blood of the same man parts; but what the immediate com- is not precisely similar in disease to position is—that is to say, in what what it was in health, or at different forms these atoms exist—we do not epochs of life. The iron which cirknow so well. The elementary com

culates in the veins of the embryo, is position of ox blood, when all its more abundant than the iron in the water is removed, is as follows :- veins of the mother; and this quantity

declines after birth, to augment again Carbon,

519.50

at puberty. The fats vary, in difHydrogen,

71.70

ferent individuals, from 1.4 to 3.3 in Nitrogen,

150.70 Oxygen,

213.90 1000. The blood-cells vary with the Ashes,

44.20

varying health. The albumen fluc

tuates from 60 to 70 parts in 1000, 1,000.00

the proportion being greater durThe following may be taken as the ing digestion. The fibrine, usually most approximative table of the sub- amounting to about three in a 1000, stances which form the immediate may rise as high as 7), or fall as low composition of human blood :

as 1.

Such are the chief points ascerWater,

784.00 tained respecting the blood in gen Albumen,

70.00

ral. We must now call attention to Fibrine,

2.20

123.50 | Globulin,

the different kinds of blood in the Cells, Hæmatin,

7.50 different parts of the circulation ; for r Cholesterine,

0.08 although we speak of “the blood” Cerebrine,

0.40

as if it were always one and the Seroline, .

0.02 Oleic and margaric acid,

same thing, it is, in truth, a system of Fats, Volatile and odorous fat

various fluids, a confluence of streams, ty ,

0.80 each more or less differing from the

other. The first grand division is Chloride of sodium,

familiar to all men—namely, that of

3.60 Chloride of potassium,

0.36

venous and arterial blood; the forTribasic phosphate of mer being dark purple, -" black soda,

0.20 blood,” as it is called—the latter Carbonate of soda, Salts,

0.84 bright scarlet. To many it will Sulphate of soda,

0.28

seem that this is but a distinction Phosphates of lime and

of colour - a distinction so easily magnesia,

0.25 Oxide and phosphate of effaced, that no sooner does the dark iron,

0.50 blood come in contact with the atExtract, salivary matter, urea, co

mosphere than it brightens into scarlouring matter of bile, acciden

let.

The distinction of colour is, tal substances,

however, the sign of an important 1,000.00 difference; for if venous blood be

injected into the arteries of an aniIn this table sugar is omitted, yet mal, it produces paralysis; if into we know that sugar, in varying quan- the arteries going to the brain, it tities, always exists in the blood produces syncope and death. Yet quitting the liver, where it is formed arterial blood thus injected will refrom albuminous matters, and is also vive an animal suffering from loss of generally found in blood at other blood. Between the two fluids, thereparts of the organism ; but, because fore, a profound difference exists; and this sugar rapidly undergoes trans- yet the venous blood bas only to pass formation into other substances, its through the lungs in an atmosphere amount cannot be estimated.

not overcharged with carbonic acid, But, granting that Chemistry had and at once it becomes transformsucceeded in making a perfect analy- ed into a nutrient sustaining fluid. sis, we should still have to bear in Wherefore? Analysis of the two mind that all the constituents vary detects but trifling variations in their in different individuals, and in dif- solids, the most notable of which is

Fai containing phospho

rus

5.47

the larger amount of red discs and proved to be the product of the vital the smaller amount of fibrine in ven- activity of the tissues, and as such ous blood. But in their gases an is taken up by the blood in exchange important difference is detected. In for its oxygen; for if the nerves both there are nitrogen, oxygen, car- which supply a limb be cut, and vital bonic acid, and ammonia, either free, activity be thus arrested, the current or combined so feebly that they are of blood will not be darkened ; preeasily disengaged. The quantity of cisely as it will not be brightened in nitrogen is much the same in both ; its passage through the lungs, if there that of ammonia probably does not be a surplus of carbonic acid in the vary, but the oxygen and carbonic air. The experiments of Bruch * are acid

vary considerably. Indeed, very instructive on this point. He there is a notion current in popular found that blood saturated with oxyworks that venous blood contains gen became darker in vacuo, while carbonic acid, and arterial blood blood saturated with carbonic acid oxygen-that being the difference did not change colour. between the two fluids. But every What causes the change of colour physiologist knows that both fluids when venous blood is submitted to contain large amounts of both gases, oxygen? Formerly it was held to be the difference being only in the rela- due to the iron in the discs ; but the tive amounts contained in each. The iron may be removed without this experiments of Magnus were for a removal affecting the phenomenon ; long while held to be conclusive of so that the opinion now held is that the opinion that arterial blood con- the change of colour is due solely to tained absolutely more carbonic acid the difference in the form of the than venous blood, although in rela- discs, which become brighter as they tion to the amount of oxygen, the become more concave, and darker as amount was less; that, in short, it they become more conver. Oxygen contained more of both gases, but the renders them concave, carbonic acid larger proportion of oxygen gave it renders them convex. its distinction. Recent investigations Arterial blood is everywhere the have considerably shaken this conclu- same : it is one stream perpetually sion, but they leave unaltered one re- flowing off into smaller streams, but sult-namely, that arterial blood con- always the same fluid in its minutest tains a large amount of carbonic rills as in its larger currents. Not acid, and a still larger amount of so venous blood. That is a confluoxygen.

ence of many currents, each one Where does the oxygen come from? bringing with it something from the The atmosphere.

Where does the soil in which it arises ; the streams carbonic acid come from? The tis- issuing out of the muscles bring subsues. The blood which flows to the stances unlike those issuing out of tissues is scarlet, but in the capil- the nervous centres; the blood which laries it parts with some of its oxy- hurries out of the intestine contains gen; and as it flows from the tis- substances unlike those which hurry sues it is dark, and will become scar- out of the liver. The waste of all the let again on its passage through the organs has to be carried away by the lungs. When we know that arterial vessels of the organs. Wondrously blood contains carbonic acid as well does the complex machine work its as oxygen, the idea suggests itself, many purposes : the roaring loom of that on parting with some of this Life is never for a moment still, oxygen it might assume the dark weaving and weaving, colour, owing simply to the carbonic

“ Geburt und Grab, acid retained; but this idea is set

Ein ewigos Meer, aside by the fact that unless an ex

Ein wechselnd Weben, change take place, no oxygen will

Ein glühend Leben." + he liberated. "The carbonic acid is Difficult it is for us to realise to

* SIEBOLD ů KÖLLIKER: Zeitschrift für wissenschaftliche Zoologie, iv. 273.

+ Paust. “Birth and the grave, an eternal ocean, a changing motion, a glowing life."

course.

ourselves the fact of this incessant the vessels of the trunk and head, torrent of confluent streams coursing until the fluid, escaping from the through every part of our bodies, veins, had only a pale red or yelcarrying fresh

fuel to feed the mighty low colour. The quantity of blood flame of life, and removing all the remaining in the body was then calashes which the flame has left. Sud- culated by instituting a comparison den agitation, setting the heart into between the solid residue of this pale more impetuous movement, may make red aqueous fluid and that of the us aware that it is throbbing cease- blood which first escaped. The livlessly ; or we may feel it beating when ing body of one of the criminals the hand is accidentally resting on it weighed 60,140 grammes,* after deduring the calm hours of repose; but capitation 54,600 grammes, conseeven then, when the fact of the heart's quently 5,540 gram nies of blood had beating obtrudes itself on conscious- escaped ; 28.560 grammes of this ness, we do not mentally pursue the blood yielded 5.36 of solid residue ; current as it quits the heart to dis- 60.5 grammes of sanguineous water, tribute itself even to the remotest collected after the injection, yielded part of the body, and thence to re- 3.724 of solid substances. There turn once more—we do not follow its were collected 6050 grammes of the devious paths, and think of all the sanguineous water that returned from mysterious actions which attend its the veins, and these contained 37.24

If for a moment we could of solid residue, which corresponds with the bodily eye see into the to 1,980 grammes of blood. The estiframe of man, as with the micro- mate, therefore, turns out as follows: scopo we see into the transparent 5,540 grammes escaped after decapiframes of some simpler animals, what tation, and 1,980 remained in the a spectacle would be unveiled ! body, thus making 7,520 grammes ; Through one complex system of ves- in other words, the weight of the sels we should see a leaping torrent whole blood was to that of the body of blood, carried into the depths, and nearly in the ratio of 1 to 8. It is over the surfaces of all the organs, obvious from the account of the exat the rapid rate of one foot in every periment that only an approximation second, and carried from the depths could be arrived at. And Bischoff's and surfaces through another system more recent investigations on the of vessels, back again to the heart : body of a criminal, carefully weighed yet in spite of the countless chan- before and after decapitation, lead to nels and the crowded complexity of the conclusion that the blood amountthe tissues, nowhere should we de- ed to 9} lb., or exactly one-fourteenth tect any confusion, nowhere any fail- of the whole body.+

This nearly Such a spectacle as this is corresponds with his former investiunveiled to the mental eye alone, and gations, which gave the weight as we cannot contemplate it, even in one-thirteenth of the whole body. thought, without a thrill.

If we say ten pounds for an adult It is a natural question, and often healthy man, we shall probably be as asked, but difficult to answer, What near the mark as po ble. The quantity of blood circulates every quantity, however, necessarily varies minute in our bodies? The many esti- in different persons, and seems from mates which have been made need not some calculations to be greater in here be given: only those of Lehmann, women than in men. In the seal its Weber, and Bischoff now command quantity is enormous, surpassing that general attention. Lehmann says of all other animals, man included. that his friend Weber aided him in In former days, blood-letting was determining the quantity of blood one of the “heroic arms" of medical in two decapitated criminals. The practice; and it is sometimes almost quantity which escaped was thus appalling to read of the exploits of estimated : Water was injected into practitioners. Haller mentions the

ure,

A Gramme is somewhat more than 15 grains.
+ See his Memoir in SIEBOLD Ŭ KÖLLIKER : Zeitschrift, ix. 72.

case of a hysterical woman who was That night he slept well. The ex-
bled one thousand and twenty times periment was repeated on the suc-
in the space of nineteen years; and a ceeding day; he slept quietly, and
girl at Pisa is said to have been bled awoke sane !
once a-day, or once every other day, Great was the sensation produced
during several years. A third case he by this success. Lower and King
mentions of a young man who lost were emboldened to repeat it in Lon-
seventy-five pounds of blood in ten don. They found a healthy man
days ; 80 that if we reckon ten pounds willing to have some blood drawn
as the utmost which the body con- from him, and replaced by that of a
tains at any given period, it is clear sheep. He felt the warm stream
that this young man's loss must have pouring in, and declared it was so
been repaired almost immediately. pleasant that they might repeat the
In truth, the blood is incessantly be experiment. The tidings flew over
ing abstracted and replaced during Europe. In Italy and Germany the

.
the ordinary processes of life. Were plan was repeated, and it now seemed
it not continually renewed, it would as if transfusion would become one
soon vanish altogether, like water more of the “beroic arms” of medi-
disappearing in sand. The hungry cine. These hopes were soon dashed.
tissues momently snatch at its mate- The patient on whom Denis had
rials as it hurries through them, and operated again went mad, was again
the active absorbents momently pour treated with transfusion, and died
fresh materials into it.

during the operation. The son of the In contemplating the loss of blood Swedish minister, who had been befrom wounds or hæmorrhage, and in nefited by one transfusion, perished noting how the vital powers ebb as after a second. A third death was the blood flows out, we are naturally assigned to a similar cause ; and in led to ask whether the peril may not April 1668 the Parliament of Paris be avoided by pouring in fresh blood. made it criminal to attempt transThe idea of transfusion is indeed fusion, except with the consent of the very ancient. But the ancients, in Faculty of Paris. Thus the whole spite of their facile credulity as to thing fell into discredit, to be revived the effect of any physiological experi- again in our own day, and to be ments, were in no condition to make placed at last on a scientific basis. the experiment. They were too It will immediately occur to the unacquainted with physiology, and physiologist who reads the accounts with the art of experiment, to know of these experiments, that transfusion how to set about transfusion. Not was effected on the supposition that until the middle of the seventeenth the blood of all quadrupeds was the century had

a preparation been same, and that it was indifferent made for such a trial

The ex

whether a man received the blood of periments of Boyle, Graaf, and another man, or of a sheep or calf. Fracassati, on the injection of va- This supposition was altogether errorious substances into the veins of neous. The more rigorous investianimals, were crowned by those of gations of the moderns have estabLower, who, in 1665, injected blood lished that only the blood of animals into the veins of a dog. Two years of the same species can be translater a bolder attempt was made on fused in large quantity without fatal

A French mathematician, results. The blood of a horse is Denis, assisted by a surgeon, having poison in the veins of a dog; the repeated with success the experi

blood of a sheep is poison in the ments of Lower, resolved to extend veins of a cat; but the blood of a the new idea. It was difficult to get horse will revive the fainting ass. a human patient on whom the plan From this it follows, that when could be tried ; but one evening a transfusion is practised on human bemadman arrived'in Paris quite naked, ings, human

blood must be employed; ; and he was daringly seized by Denis and so employed, the practice is in as the fitting subject for the new ex- some urgent cases not only safe, but periment. Eight ounces of calf's forms the sole remedy. Blundell has blood were transfused into his veins. the glory of having revived and vin

а

man.

a

dicated this practice,* and he has is not all. The experiments of M. seen his idea amply confirmed. B6- Brown-Séquard establish the importrard cites fifteen distinct cases of ant fact that it is to the oxygen carhæmorrhage in which transfusion has ried by these cells that we must saved life.+

attribute their nutritive agency, and Seeing that blood has thus a power to the carbonic acid carried by them of reanimating the failing body, it is that we must attribute their stimulatnatural we should inquire to which ing agency. I Blood has two offices : element of the blood this is due- to it furnishes the tissues with their pathe cells or the plasma ? We know bulum, and it stimulates them into that it is only necessary to withdraw activity. Unless the tissues be enblood from a part, or prevent its ac- dowed with certain vital properties cess by a ligature round the arteries, they cannot be stimulated into actiand the part gradually loses all its vity; and when stimulated, this activital properties ; but even after the vity brings about a destruction, which rigour of the muscles announces death, must be repaired. If stimulus be apwe have only to readmit the blood plied without equivalent nutrition, by removing the ligature, and the the force is soon exhausted. This vitality will be restored. Now it has double office the blood performs, acbeen ascertained that the plasma of cording to M. Brown-Séquard, chiefly the blood, deprived of its cells and through the oxygen, as the agent of fibrine, has no reanimating power nutrition, and of carbonic acid, as the when injected, being in fact not more agent of excitation. Without accepteffective than so much warm water. ing his conclusions in all their absoIt has also been ascertained that luteness, we may accept thus much blood, deprived of its fibrine only, of them, for we see him operating on produces the same effect as pure dead animals, or dead parts of aniblood, whereby it appears that as mals, by means of venous blood neither the plasma nor the fibrine charged with oxygen, and producing possesses the vivifying power, that therewith precisely the same effects power must belong to the cells.' This as with arterial blood; and we see is a great step gained, but the rest- him showing that arterial blood, less spirit of inquiry cannot content charged with carbonic acid, acts preitself with such a gain, and it asks, cisely as venous blood. The concluwhat gives to the blood-cells this sion, therefore, is obvious, that the specific power ? Let us see the difference between the two fluids is answer that can be made to such a simply owing to the difference in their question.

amounts of oxygen. He takes the We know that the cells carry the blood from a dog's vein, and the oxygen, either in slight combinations blood from its artery, whips both till or free, as in vesicles. We know the fibrine be extracted, and till both this, because we find that the plasma have become equally scarlet from the is unable to absorb much more than absorption of oxygen. He then inone per cent of its volume of oxygen, jects one of these fluids into the right whereas the blood, containing cells, femoral artery of a dead rabbit, in absorbs from ten to thirteen times which the rigidity of death has set in that amount. The change of colour for ten minutes, and the other fluid they exhibit as they take up or give into the left femoral artery. The reout oxygen, and the fact that, if they sult is precisely similar in both limbs, are placed in a vessel containing air, namely, in about five minutes both they absorb oxygen from that air, recover their muscular irritability, whereas the plasma does nothing of which they both retain for twenty the kind, are proofs of the cells being minutes. Repeating this experiment the transporters of oxygen. But this with blood drawn from vein and ar

* BLUNDELL: Experimer on the Transfusion of Blood," Medico-Chirur. Trans. 1818, p. 56.

+ BERARD : Cours de Physiol., iii. 220. It is from this work and the Leçons of MILNE EDWARDS that all the details on this subject in the text have been taken.

# BROWN-SEQUARD : Journal de la Physiologie, 1858, i. 91.