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tery, but charged with carbonic acid causes an activity which is soon spent, instead of oxygen, he finds a similar because it cannot be reproduced.” result as to the exciting power. Hav- Even should we accept to the full ing thus made clear to himself that, the ingenious hypothesis just proas respects nutrition and excitation, pounded, we must guard against an there is no other difference between exaggeration of its application. Oxyarterial and venous blood than is gen may be the one chief condition assignable to their differences in the for that exchange between the blood amount of oxygen and carbonic acid and the tissues which constitutes contained in each; that venous blood, Nutrition, and without a due supply charged with oxygen, acts precisely of oxygen Nutrition may be brought as arterial blood; and that arterial to a stand-still; but we shall greatly blood, charged with carbonic acid, err if we suppose that oxidation is acts precisely as venous blood, M. itself the process of Nutrition, or that Brown-Séquard proceeds with his de- the cells are the sole agents. The monstration, that unless the blood be albumen, the fats, and the salts which highly oxygenated it has no power of the tissues draw from the blood, are nourishing the tissues; and unless it not drawn from the cells, but from be highly carbonised, it has no power the plasma. It is, therefore, quite of stimulating them. We cannot here possible, indeed M. Séquard's expeafford sufficient space to give any riments render it eminently probable, account of the experiments by which that the blood-cells, by their oxygen, these conclusions are reached, and furnish the indispensable condition must refer the curious reader to the of Nutrition, the pabulum being furmemoir itself.* But as the idea of nished by the blood-plasma. "It is the stimulating power of the blood also probable that the cells, by their residing chiefly in the carbonic acid, carbonic acid, furnish the condition will be novel and startling to most of nervous and muscular excitement; physiological readers, it may be use- so that arterial blood, containing ful to mention one of the experiments. more than its usual amount of carA rabbit was suffocated; and, as bonic acid, causes an excess of the usual in such cases, the intestine stimulating over the repairing proexhibited very powerful disorderly cesses. This will account for the movements. Into a coil of this agi- greater cerebral excitement succeeded tated intestine he injected some ve- by languor consequent on exposure nous blood highly oxygenated. Im- to the vitiated atmosphere of a theamediately the movement ceased. He tre, a ball-room, or a lecture-room. then injected arterial blood highly Such is the wondrous fluid we carbonised, and the movements were name Blood, and such its properties, at once resumed. Again he injected as far as Science hitherto has learned oxygenated blood, and again the them. Before quitting our survey, movements ceased, to appear on the it will be desirable to say a few second injection of carbonised blood. words respecting the relation blood " It is possible," he says, “ to produce bears to Nutrition, since that relatwo conditions of the organism essen- tion is not generally understood. tially different, one of which consists Every one knows that all the tissues in the presence of a greater amount are nourished by the blood. But in of oxygen than usual, both in the what way is this effected ? Blood, in venous and in the arterial blood, the itself, is perfectly incapable of nourother of which consists in the pre- ishing the tissues—so incapable that, sence of an excess of carbonic acid if it be poured on them from the rupin both fluids. In the first of these ture of a vessel, it hinders nutrition, conditions, life ceases in spite of the and acts like a foreign substance. extreme energy of the vital proper- Accordingly, we see it rigorously exties, simply because the stimulating cluded from them, shut up in a syspower of the blood is insufficient. In tem of closed vessels; but as it rushes the other of these conditions, the along these vessels, certain its elestimulating power, being excessive, ments ooze through the delicate walls

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* Journal de la Physiologie, i. 95.

of the vessels, and furnish a plasma from our blood. The hair in its confrom which the tissues are elaborat- stant growth not only serves its pured. In exchange, certain products poses as hair, but also as a source of of waste are taken up by the blood, removal from the blood of the various and carried to the organs of excre- constituents which form hair. “And tion. An image may render the pro- this excretion office appears in some cess memorable. The body is like a instances to be the only one by which city intersected by a vast network of the hair serves the purpose of the canals, such as Venice or Amster- individuals; as, for example, in the dam; these canals are laden with fætus. Thus in the foetus of the barges which carry to each house the seals, that take the water as soon as meat, vegetables, and groceries need- they are born, and, I believe, in those ed for daily use; and while the food of many other mammals, though reis thus presented at each door, the moved from all those conditions canal receives all the sewage of the against which hair protects, yet a houses. One house will take one perfect coat of hair is formed within kind of meat, and another house an- the uterus, and before, or very shortother kind, while a third will let the ly after birth, this is shed, and is remeat pass, and take only vegetables. placed by another coat of wholly But as the original stock of food was different colour, the growth of which limited, it is obvious that the de- began within the uterus. Surely in mands of each house necessarily affect these cases it is only as an excretion, the supplies of the others. This is or chiefly as such, that this first what occurs in Nutrition : the mus- growth of hair serves to the advancles demand one set of principles, the tage of the individual.” Mr Paget nerves a second, the bones a third, also applies this principle to the exand each will draw from the blood planation of the rudimental hair those which it needs, allowing the which exists all over our bodies, and others for which it has no need to to that of many other rudimental pass on.

organs, which subserve no function This leads us to notice a luminous whatever. He also, without appaconception, attributed by Mr Paget rently being aware of Wolff's ideas to Treviranus, but really due to Cas- on this point, applies it to the explapar Friedrich Wolff, whose doctrine nation of the embryonic phases. "For of epigenesis reposes on it; namely, if it be influential when all the orthat each single part of the body, gans are fully formed,” he says, " and in respect of its nutrition, stands to are only growing or maintaining the whole body in the relation of a themselves, much more will it be so secreting organ.” Mr Paget has illus- when the several organs are succestrated this idea with his accustomed sively forming. At this time, as each felicity.* Every part of the body nascent organ takes from the nutritaking from the blood those sub- tive material its appropriate constistances which it needs, acts as an ex- tuents, it will co-operate with the cretory organ, inasmuch as it re- gradual self-development of the blood, moves that which, if retained, would to induce in it that condition which be injurious to the nutrition of the is essential, or most favourable, to rest of the body. Thus the polypes the formation of the organs next in excrete large quantities of calcareous order to be developed.'

This prinand silicious earths : in the polypes ciple further enables us to understand which have no stony skeleton, these how the existence of certain mateearths are absolutely and utterly ex- rials in the blood may determine the creted;

but in those which have a formation of structures in which these skeleton, they are, though retained materials are to be incorporated; and within the body, yet as truly excreted it enables us to understand the from the nutritive fluid and the other stitutional disturbance," or general parts as if they had been thrown out state of ill health, which arises from and washed away. In the same man- some local disturbance, such as a cold ner, our bones excrete the phosphates in the head; for," if each part in its

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PAGET : Lectures on Surgical Pathology, i. 24, et seq.

normal nutrition is an excreting or- meates and nourishes much in the gan to the rest, then cessation or way that the blood-plasma nourishes perversion of nutrition in one, must, the substance of the more complex through definite changes in the blood, animals. But in the simplest aniaffect the nutrition of the rest.” How mals there is not even this approach evidently the special condition of the to blood. There is no liquid product organism determines the growth or of digestion, for there is no digestion decrease of certain organs, may best at all, the water in which these anibe seen in the sudden development mals live carrying organic matter in of the beard and the voice as puberty solution ; this permeates the subapproaches. Birds in the pairing stance, and is assimilated : thus does season acquire their most brilliant the water play the part of blood, plumage, and express the tumult of carrying the food, and carrying away their emotions in perpetual song. the waste." Stags at the same epoch develop their Let the speculative eye traverse the antlers, and make the forest_ ring marvellous scale of created beings with their hoarse barking. Mr Paget upwards, from the simplest to the justly says—“Where two or more most complex, and it will observe that organs are thus manifestly connected Assimilation first takes place by the in nutrition, and not connected in direct relation of the organism to the exercise of any external office, the surrounding medium; next artheir connection is because each of rives the interposition of agencies them is partly formed of materials which prepare the food for the higher left in the blood on the formation of effects it has to produce, and instead the other." *

of relying on organic substances in Does not this throw a new light solution, the organism is seen extractupon the blood ? and do you not ing nutriment from other organtherein catch a glimpse of many pro- isms; finally is seen the operation cesses before entirely obscure? It of still more complicated agencies, assures us that the blood is not which impress on the digested food "flowing flesh”-la chair coulante- still higher characters, converting it as Bordeu called it, to the great de into blood. This blood is retained in light of his successors; nor is it even a system of vessels everywhere closed. liquid food. It is an organic struc- Yet, in spite of the absence of orifices ture, incessantly passing through or pores, it is distributed impartially changes, which changes are the con- to the most distant parts of the orditions of all development and ac- ganism, and it is distributed accordtivity: The Food and Drink which ing to the momentary requirements we take become subjected to a com- of each part, so that when an organ plicated series of digestive processes. is called upon to put forth increased The liquid product of Digestion is energy, there is always an increase carried into the blood-stream, under- of food sent to supply that energy. going various changes in its route. If the stomach has been quiescent It is now blood; but other changes for hours while the brain has been supervene before this blood is fitted active, the regulating power of the for the nourishment of the tissues; circulation has adapted the supply and then certain elements pass from of blood to each organ; and no sooner it through the walls of the capilla- will the stomach be called upon to ries to be finally assimilated by the exert itself, than an abundant supply tissues. In the simpler animals, the of blood will instantly be directed to liquid product of digestion is itself the it. This simple and beautiful fact immediate agent of Nutrition, and in the animal economy should warn does not pass through the interme- men against the vicious habit of diate stage of blood. It escapes from studying at or shortly after meals, the digestive canal into the general or of tasking the brain when the substance of the body, which it per- stomach is also tasked.

* PAGET, p. 32.
+ This was shown at length in a former number of Maga, June 1857.

RELIGIOUS MEMOIRS.

THERE are few things so strange, one hand, that the highest producarbitrary, and unaccountable, as that tions of genius are unappreciated by amount of common liking and re- the multitude ; and it is still greater gard

which we call popularity. folly, on the other, to make success Sometimes it answers to the touch an infallible proof of desert. The of real genius, with a unanimity and decisions of the popular tribunal of readiness which, for the moment, literary criticism, are not at all unmight prompt us to believe in its like the decisions of that jury which decision as the true and infallible regulated its verdicts on the purely test of reputation ; but ere we have impartial principle of alternation, had time to do more than observe and said guilty and not guilty time the instinctive and universal impulse about, with a noble indifference to of this recognition, the popular fancy such small matters as facts or evihas gone mad after some silly won- dence. If we are disappointed of der, or raised to its highest honours the verdict ourselves, we cannot consome superficial and worthless pro- sole our mortification by the thought duction, which we should have sup- that it is always in the wrong, and posed incapable of moving to any never justly rewards a generous amsentiment whatever any single hu- bition : but that it is perfectly capriman mind. Nothing can possibly cious, unreasoning, and unexplainbe more puzzling than this strange able; that it is simply impossible to perversity. The applauding cla- form any conclusion beforehand as mour of the vox populilet disap- to what its judgment may be ; and pointed men say what they will that, often right, it still preserves a is, after all, the culmination and delightful independence, and keeps apotheosis of fame. Yet the same resolutely clear of the imputation of clamour rushes with unreasoning being always so, nobody acquainted lavishness after books and persons with modern literature or opinions which have no more claim to fame, ever deny. than has the smallest newspaper

It is impossible to avoid thinking critic who professes to dispense it. this, when one contemplates the In the world of books one has but to enormous amount of good books curglance over the title-pages of those rent and popular at the present time which bear the honours of many -we might add of bad books alsoeditions, to perceive the extraordi- for the religious and the irreligious nary freaks of this popularity, which are almost equally independent of bestows upon the most frivolous those ordinary qualities which achieve and commonplace performances ap- the rewards and honours of literaplause as great as that with which ture. But we will not compare the it celebrates the most eminent penny novels, disreputable and un. works of genius. This fantastic fragrant, with those trim octavos and uncertainty leaves us totally unable duodecimos which throng the tables either to receive or to deny the of religious publishers, and pass by authority of a popular success. It the thousand into homes of respecmay be bravely won and honestly tability. These pious volumes are, deserved-a triumph of real and for the most part, as excellent in ingenuine art ;, or it may be a hap- tention as they are important in subhazard “hit,” which it is impossible ject—they are, indeed, only too much to give any reason for, and at which bent upon the universal edification authors and readers are alike asto- of their audience, and are reluctant nished; but so purely unaccount- to record the merest passing inciable are the vaticinations of this dent without weighing it down with oracle, that no one is justified in the heavy overbalance of a spiritual making a general conclusion as to lesson. When we say pious volumes, the worth or worthlessness of its we beg that no one will suppose we verdict. It is folly to say, on the mean to imply the faintest approach to a scoff. Their piety is the only class of books so largely sold, and so genuine quality in the great mass of universally, possessed. The most these publications; and we must famous fictions of the day are in less presume it is for that sole sake that demand than those pieces of religious many really prefer, and many more biography of which, were the names think it right to receive, works which struck out, one might read a score have scarcely a claim to be called without being able to tell where one literature, save the mere fact that terminated and another began; and they have been written and are neither Thackeray nor Dickens can printed. Their piety alone might count half as many editions as have induce us to pass over without com- fallen to the lot, for example, of the ment the other imperfections of this Memorials of Captain Hedley Vicars class of writing; but we cannot sup- -a little volume fully representing pose that it is any real advantage to the character of its kind. We do the religious community to put up not approach this subject with either with these publications, out of ten contempt or levity-far from that, derness for the sentiment of godli- we speak sadly, knowing that we ness which is presumed to pervade shall be obliged to condemn what them. This has been, perhaps, done hundreds of better people than too much already. We have been we applaud and love ; yet it does afraid to incur the reproach of a seem so strange an enigma why the want of spiritual appreciation, and a greatest subjects in the world should general dislike to religious writings, be treated with the poorest language; and so have been obliged to swallow why lives which, in the living, were the endless repetition, and flat and noble, generous, and above praise, unnatural representations of life, should become, in the telling, only conveyed to us in books which no- tiresome and tedious; and why mula thing but their piety could have en- titudes, great enough to convert prititled to a moment's consideration. vate applause into general popularity, This is rather hard upon the unfor- should be pleased to have it so—that tunate critic: he reads, because he we cannot refrain from inquiring why respects the religious feeling of the and how this strange paradox is ? writer; he condemns, because human We beg to premise, however, in the nature cannot stand the manner of first place, that we entirely leave out the performance; and he is imme- legitimate sermons, and all the effudiately set down as a profane person, sions of all the authorised teachers of who cannot be supposed to appre- all the churches. What we have to ciate the true beauty of holiness. deal with is specially the crowd of Perhaps this hard dealing is one of pious memoirs, the floating light (or the reasons why the common mass heavy) literatureofthereligious world. of religious literature is so destitute Memoirs of pure minds, of noble of ordinary literary qualities — for lives, of hearts warm with all the men who love the matter have been fervour and sunshine of the Gospel afraid to incur the odium of criticis- let us do homage to those young ing the manner of those productions, saints, those virgin confessors, those and the censorship has been left to true soldiers of our Lord. It is no hands indifferent, and passed by with reproach to them that friends make a sneer or a laugh according to the merchandise of their devout letters, temper of the moment. Yet it is their pious sayings, and the secret impossible to overestimate the im- life which they lived with God-or portance of this kind of writing. that an unwise love beguiles its grief For one thing, it conveys to many a by making into talk, and throwing totally erroneous idea of religious irreverently open, the innermost sancpeople, and of the effects of personal tuary of their souls. They are the godliness, which is a great misfor- greatest sufferers by the operation. tune; and it cannot fail to depreciate Yet it is wonderful to perceive with the cultivation, refinement, and good what ease all features of human intaste which we fondly expect must dividuality can be obliterated from accompany our outside progress and the record which professes to tell us increasing comfort ; for there is no how one and another, real men and

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