ON THE ACTUAL SPECIFIC INDIVIDUALITY OF THE ALBUMINOID PROXIMATE PRINCIPLES. THE ALBUMINOIDS. THE PHENOMENON OF COAGULATION. THE ALBUMINOIDS OF THE FIBRIN. THE ALBUMINOIDS OF THE SERUM. HAEMOGLOBIN. HAEMOGLOBIN AND OXYGENATED WATER
To solve the problem of the spontaneous coagulation of the blood, it is necessary to know not only the three anatomical elements of this humor, but also the composition of the medium in the midst whereof they live, because there are to be found united the conditions of their existence.
Let us admit—what will be proven—that, in accordance with the hypothesis of Hewson, of Milne Edwards and of Dumas, fibrin does not exist dissolved in the blood, and further that it is connected with what we have called fibrinous microzymas. We then recognize that the really liquid part of the blood contains all its components, including therein the albuminoids, in a state of perfect solution, as in the serum separated from the clot.
In 1815 it was supposed that the serum of the blood contained albumin as the only albuminoid matter, and this was not only identified with the white of an egg, but with the albumen of the serous fluid of the pericardium and of the ventricles of the brain, with chyle, and even with pathological serous fluids: such as that of dropsy, of blisters, etc.1 And these identifications were based solely upon a single character, coagulation.
1. Thenard, Traite de chimie, Vol. III, p. 432 (1815).
Even to-day it is contended that two solutions contain the same albumin when they are coagulable at about the same temperature. But the phenomenon of coagulation has been so abused that it has become necessary to define it accurately.
The phenomenon of coagulation. At first the term coagulation was applied to the passage of the blood from a liquid to a solid state, in the same sense that one said of a liquid which solidified, of a vapor which condensed into a liquid,—that it coagulated. Fourcroy said of the white of egg, of the blood serum, etc., that they are concresciblea by the application of heat because they contain albumin. But in process of time, to the notion of coagulability, chemists added that of insolubility; to coagulate became for the albuminoids the correlative to becoming insoluble. For instance, when the white of egg forms into a solid mass in a hard boiled egg, it is said to have coagulated, to have become at once solidified and insoluble throughout; but as will be seen presently it is not so with the blood when that is said to be spontaneously coagulated.
a. [Obsolete; from the Latin concrescere, to grow together, hence to solidify.—Trans.]
When coagulation was thus strictly defined in a chemical sense, the insolubility of the coagulated substance was only considered relatively to water as the solvent; solubility before coagulation was also relative to water. But we shall see that the idea should be completed by extending it to other solvents.
In the present state of science, for instance, the name fibrin is given not only to that which I have just studied, that of the blood, the general phlebotomy of adults, but also to that of the arterial or venous blood, without regard to the region of the vascular system from which it is taken, without distinction as to age; that of the chyle, that of the lymph or even of pathological serosities. And this fibrin was regarded as coagulated albumin without regard to the special action of fibrin upon oxygenated water, nor, as we shall see, of its own coagulability.
A rapid review of the history of albuminoid matters will enable us to understand how, in 1875, it came to be supposed that fibrin was only a stage in the transformation or alterations of albumin.
Under the influence of Gay-Lussac and of Thenard, of Mulder and of Dumas, chemists had admitted a certain number of nitrogenous matters of animal or vegetable origin as specific, not only when they were a little different, but even apparently identical in their centesimal elementary composition. These matters Dumas called "neutral nitrogenized matters of the organization," recalling thereby an old classification of Thenard. At last they were called albuminoids, comparing them to albumen, or white of egg, taken for a type, because of certain common properties and of some resemblances in composition. The notion of specificity prevailed up to 1840; after that, in spite of Berzelius, the singular idea of the substantial unity of these substances seemed to prevail. This is how it came about.
It will be remembered that Bouchardat gave the name of albuminose to the fibrinous matter dissolved by very dilute hydrochloric acid. The reason for the invention of this new word is a curious one. Biot had observed that the watery solution of the white of egg deviated the plane of polarization of polarized light to the left; Bouchardat, having found that the hydrochloric solution of fibrin also deviated the same plane of polarization to the left, concluded that "as the soluble principle of fibrin is identical with the dominant matter of the albumen of the egg, I propose for this pure substance the name of albuminose." Then dissolving in very dilute hydrochloric acid various other analogous substances and observing the same results in solutions thus obtained, he generalized as follows: "The fundamental principle found in the fibrin, in the albumen of egg, in the serum of blood, in the gluten of cereals, in casein, is always the same; it is albuminose, mixed or combined sometimes with earthy matters, phosphates of lime and of magnesia, sometimes with alkaline salts, sometimes with fatty matters, which mask their essential properties. If this ephemeral combination be destroyed by a really inappreciable proportion of acid, the albuminose solution is then found with identical properties, exactly similar chemical reactions, similar action on polarized light, always deviating to the left, the energy whereof, other things equal, is always proportioned to the weight of the substance dissolved.1
The above amounts to saying that the albumen of the white of egg, that of serum, the essential matter of gluten, of casein and of fibrin, are the same substance, possessing the same rotatory power.
We shall see how, even as to fibrin, to what extent the observation of Bouchardat was superficial and how he deceived himself in generalizing it. He deceived himself so strangely that he did not think for a moment that he had to do with hydrochloric combinations, believing that the quantity of hydrochloric acid of his solvent was inappreciable, etc. The chemists were equally careless. Ch. Gerhardt adopted Bouchardat's point of view and extended it.2 In Germany, especially, a legion of chemists maintained the substantial identity of these matters; P. Schutzenberger (a native of Holland, domiciled in France) adopted it. It was because they knew very little about the chemical constitution of albumen; so little that Ch. Gerhardt consigned albuminoid matters to a place below asphaltes and bitumens, and that in the general confusion M. Naquet thought that albuminoid substances did not belong to the domain of chemistry, but to that of physiology, as remains of organs.
But in 1856, while I was busied with the researches which resulted in the discovery of the microzymas, in a work on the source of urea in the organism,3 by arguments drawn
1. C. R.. Vol. XIV, pp. 966-967 (1842).2. Ch. Gerhardt, "Traite de chimie organique." Vol. IV, p. 436 (1856).3. "Essai sur les substances albuminoides et sur leur transformation en l'uree." These de la Faculte de medecine de Strasbourg. (2d S.). No. 376 (1856).
as much from chemistry as from physiology, I had maintained the specific plurality of the albuminoids and demonstrated that these substances, animal and vegetable alike, produce urea by decomposition following a phenomenon of oxydation. In this work I succeeded in expressing the chemical constitution of albumin and of the albuminoids in general, regarded as proximate principles. I showed that their molecules were very complex, the most complex known, inasmuch as formed of numerous non-complex molecules of the fatty and aromatic series, among which were amide derivatives, amides and sulphides, in the number whereof urea was never wanting, so that if the ureides of M. Grimaux had been known I should have said that albumin is a very complex ureide. In this work I laid the foundation for the future researches which led me to the discovery that the albuminoid matters, even those regarded as proximate principles, are either mixtures, like the albumin of white of egg, or organized things, like fibrin and vitellin. The researches whereby I demonstrated analytically that there are a great number of natural albumins and albuminoids, reducible to rigorously defined proximate principles, were made the subject of examination by a commission of the Academy of Sciences and of a report by J. B. Dumas.1 It was in the memoir which is the subject of this report that is to be found the demonstration of the specific plurality of albuminoid matters, and that the doctrine of their substantial unity is an error.2
1. C. R., Vol. XCIV. The members of the Commission were Milne-Edwards, Peligot, Fremy, Cahours, Dumas reporter.2. "Memoir sur les matirees albuminoides." Recueil des memoires des savants etangers. Vol. XXVIII, No. 3, 516 pages. Imp. Nat.
Among other things, I demonstrated that the classical albumin, the white of egg of the fowl, the type to which had been referred all those matters which were identified under the name of albumin, was a mixture of three proximate principles, irreducible to one another; all three albuminoids, all three soluble and deviating the plane of polarization of light to the left, whereof two are coagulable by heat, the third not coagulable, a veritable zymas. And J. Bechamp, having analyzed, by the same method, the whites of eggs of a number of oviparous animals, birds and reptiles, discovered among them other albumens, other zymases, different from those of the egg of the fowl; so different and differing among themselves that he was able to specify the species of a bird by the albumens of its egg.1
But prejudice and partisanship are so tenacious that nothing was of any avail. Notwithstanding the report of Dumas, long afterwards, a learned physiologist held that fibrin was a proximate principle. He did so in reliance on the opinion of M. Duclaux proclaiming "the extreme mutability of albuminoid matters and the folly of the chemical specifications established in this category of organic substances,2 and again maintained that fibrin was a proximate principle.
1. J. Bechamp, "Nouvelles recherches surlesalbumines normales et pathologiqites." I. B. Bailliere el fils Paris (1887).2. Dastre, C. R-, Vol. XCVIII, p. 959. See on this subject A. Bechamp's Remarks on the note of M. Dastre under the title of "Existe-t-il une digestion sans ferments digestifs des matieres albuminoides?" C. R.. Vol. XCVIII, p. 1157 (1894). M. Dastre saw fibrin disappear, dissolved, in a solution of fluoride of sodium and concluded that it was a digestion.
It is upon such opinions that rests the assurance that fibrin is a stage in the mutations of albumin and that the albumen of milk is a consequence of another change in caseine, as asserted by M. Duclaux. All this is inaccurate and one may even say absolutely untrue, for pure albuminoid matters are fixed and are as rigorously definable and specific as any other proximate principle.
Independently of the ignorance which prevailed touching the chemical constitution of the albuminoids, that which most constributed to perpetuate these prejudices was that so little was known concerning the faculty of the albuminoids to form combinations with bases or acids, that even Dumas had held them to be neutral nitrogenous matters. It is true that Bouchardat said that they form combinations with the alkalies and alkaline earths, but said that such combinations were only ephemeral. Thenard admitted the formation of combinations with hydrochloric and sulphuric acids, but no one paid any further attention thereto. Lieberkuhn regarded the albumen of the white of egg as an albuminate of soda, but said also that casein was an albuminate of potash, etc. These kinds of combinations, under the hypothesis of substantial unity, served to explain the differences presented by these matters, compared with one another, as being soluble or insoluble. What is certain is that, at least in the animal organism, albuminoid matters are always combined with an alkali or an alkaline earth, and that further these combinations are complicated by the presence of phosphatic earths, which they dissolve. And as if to augment the confusion and force of prejudice, natural coagulations were admitted, at the same time that the insolubility of fibrin was sought to be explained by its combinations with phosphates, it was called coagulated albumen; as to the soluble albuminoids, to differentiate them they invoked coagulation by heat; those which coagulated at the same temperature were regarded as identical; casein was said to be insoluble by heat, but coagulable by acids, thus confounding a purely chemical phenomenon of precipitation with a physical phenomenon, etc.
My researches have solidly established that from those natural materials which always constitute mixtures there can be separated by means of analysis the albuminoids, proximate principles, which when isolated have an acid reaction and which unite with bases in as definite proportions as any acid, so that casein produces with sodium a neutral caseinate, and a bicaseinate, which reddens litmus paper. I also demonstrated that these substances can form combinations with hydrochloric acid and with acetic acid in several proportions. From these various combinations the albuminoid matter, whether soluble or insoluble, can always be isolated with its own proper characters and always with the same rotatory power.
But the natural albuminoid matters, even when reduced to proximate principles isolated from bases and other mineral matters with which they had been combined or mixed, are neither crystallizable, volatile nor fusible; they possess then none of the so-called constant characters employed by chemists to ascertain at once their purity and identity. How then can one make sure that the substance isolated by analysis is always identical with itself? I employed for a constant the rotatory powers employed for a like purpose by Bouchardat with the substances studied by him.
The following table gives the rotatory powers of the chief albuminoid matters on which Bouchardat experimented and disposes of the theory of the substantial unity of these matters. In the table the numbers are relative to the perceptible tint according to Biot.
We will now see how it is with a solution of blood-fibrin in very dilute hydrochloric acid.
The hydrochloric solution of fibrin, separated from its rnicrozymas, contains a mixture of albuminoid matters, soluble and insoluble in water.The limpid solution, which has been obtained with or without the addition of phenol, has a decided acid reaction and is without action on oxygenated water. The solution is really one of hydrochloric combinations with albuminoid matters, whereof the greater part is insoluble in water. In fact, on the addition of dilute ammonia so that the liquor becomes faintly alkaline, an abundant dead white flocculent precipitate is produced which, collected on a filter, well washed with distilled water, with alcohol and with ether and rapidly dried in a dry vacuum, forms a pulverulent matter. Was this the whole of the fibrin less its microzymas? If yes, the fibrin is purely and simply dissolved; if no, the solution was the result of a reaction. The alternative will be determined by dosing.
A manipulation of 60 grammes of fresh fibrin containing 11.5 gr. of matter dried at 100° C. furnished 7.6 gr. of this insoluble matter likewise dried at 100° C.; that is to say, only 66 per cent, of the weight of dry fibrin; consequently 34 per cent, of matter remained in solution. If the reaction is continued longer before separating the microzymas, the quantity of matter precipitated by the ammonia diminishes, while the dissolved portion increases.
The substance insoluble in water—the ammonia precipitates—possesses further the same elementary composition as fibrin, but it differs from the intermicrozymian substance in that it is directly soluble in very dilute hydrochloric acid, as well as in acetic acid and in ammonia. I have given it the name of fibrinine.
Further the fibrinine does not decompose oxygenated water and does not liquify fecula starch.
Among the substances which ammonia does not precipitate is one which alcohol precipitates after the separation of the fibrinine. This precipitate is a mixture; one portion is soluble in water, the other does not redissolve. I have given the name fibrimine. to that portion which is finally soluble in water.
But the part precipitated by alcohol is the smaller part of the material which ammonia does not precipitate; the rest is to be likened, more or less, to the extractives such as are found in gastric digestion; I add that the fibrimine possesses the property of liquifying starch and I regret that I did not think of examining, if it, or some of the compounds accompanying it, has the property of decomposing oxygenated water.
However that may be, the following are the rotatory powers of the hydrochloric solution of the fibrin as a whole, and of that of fibrinine and fibrimine:
Fibrin (from blood of sheep, cow and pig): Rolatory power of the hydrochloric solution of the whole of the fibrin ...................... (a) j = — 72.5°Fibrinine: Rotatory power in hydrochloric solution ........ (a)j — 67°.4Fibrimine: Rotatory power in aqueous solution .................(a) j = — 80°1
A comparison of these various and different rotatory powers, answering to other properties, not less different, of the bodies which possess them, is sufficient to show that the identification made by Bouchardat, which led him to believe that there was a substantial unity among albuminoids, had no foundation in the real nature of things. Nevertheless it
1. To complete these comparisons, in order to give a better understanding of the specific individuality of each albuminoid proximate principle, and to show still further the value of the new method of research, which, for shortness, I call the antiseptic method. I add the following: We know that fibrin, left to itself in carbolated water, changes while dissolving in great pan without becoming fetid, leaving a residue of microzymas enveloped in an insoluble albuminoid atmosphere. In short, while spontaneously transforming, fibrin produces some dissolved materials and others insoluble. The whole of the dissolved portion, albuminoid and others not volatile, had a rotatory power (a)j = — 29" to — 30°, which proves that under these conditions the soluble products are different from those formed in the change on contact with very dilute hydrochloric acid. Among the dissolved products, which together have the above rotatory power, were one zymas and several soluble albuminoids, coagulable by heat and having different rotatory powers in fact, from those of the hydrochloric solution. (See "Memoire sur les matieres albuminoides," p. 425.) More than ten years after the report of Dumas and the publication of my memoir on the albuminoid matters, a learned physiologist, M. A. Dastre, reached the same conclusions on applying the antiseptic method to the study of fibrin. He also found, in effect, that crude fibrin, "in contact with antiseptic salt solutions (fluoride and chloride of sodium) does not merely dissolve, but is transformed" into divers substances called globulines, proteoses, propeptones, peptones, as it does under the influence of gastric juice. M. Dastre found also that the spontaneous transformation of fibrin resulted in the formation of soluble and insoluble products without taking the microzymas into account, and further he generalized by applying the same method to crude albuminoid substances without other distinction, and without specifying the nature of the products formed, for the words, peptone, pro peptone, proteose, globulines, are applied to a great number of very different things. To show this assertion is well founded, here are the rotatory powers of the soluble products of digestion of some albuminoid matters digested by the gastric juice of the dog:
was upon this identification and on the results of elementary analyses made upon mixtures and not on real proximate principles that was based the opinion which regarded fibrin as coagulated albumen, or as a stage in suppoitious changes in the albumen of the white of egg. Although it has been ascertained that this albumen, coagulated or not, did not set free oxygenated water, this enormous difference was disregarded, as well as the fact which followed the incomplete solution of fibrin in dilute hydrochloric acid, whence it was obvious that fibrin was not a proximate principle. Hence it is not surprising that for a long time muscle fibrin was confounded with that of blood, and that even today the fibrin obtained from blood is regarded as being the same whatever be the animal or part of the vascular systems from which it comes, even also the fibrins of chyle, of the lymph and of pathological serosities. Denis (of Commercy) had already established that certain fibrins of the veinous blood were dissolvable in a solution of saltpetre (nitrate of potash), while others, including fibrins of arterial blood, did not dissolve in it. Estor and I demonstrated that the fibrin of the blood of very young kittens liquified and disappeared in the starch which it had liquified, while its microzymas evolved. On the other hand, I found that the fibrin of ox-blood did not dissolve under the conditions specified by Bouchardat and that it was necessary to employ hydrochloric acid at 3 in the 1,000. In another experiment the fibrin of the blood of a young chicken, treated with hydrochloric acid at a 2 per thousand strength, did not swell up even after remaining a long time in the oven, and at the end of several days the acid had dissolved very little of it, and the liquid hardly produced a precipitate with ammonia. Nevertheless this fibrin decomposed oxygenated water before treatment; it decomposed it also after treatment when the acid had been eliminated by washing with water. In short, to become convinced that fibrin is a much more variable anatomical substance than a definite chemical principle, always the same, it suffices to recall the former observations of Marchal de Calvi, of Magendie, and of Claude Bernard, as well as those of J. Birot and of J. Bechamp.1
We must then erase the fibrins from the list of proximate principles to see in them only what they really are, viz., microzymian false membranes. The intermicrozymian matter of these fibrins is not probably the same in all. However that may be, it is certain that the intermicrozymian matter of the fibrin common to ox or sheep-blood is not coagulated albumin; that it is naturally insoluble, dissolving in very dilute hydrochloric acid only by a sort of auto-digestion, whereof the microzymas it contains furnish the zymas; and not only is it not a coagulated albumen, but it is itself coagulable by heat, becoming incapable of combining with dilute hydrochloric acid and of being thereafter dissolved in it.
In his report to the Academy of Sciences, Dumas did not fail to call the attention of savants to the fact that fibrin owes its property of decomposing oxygenated2 water to that part of it which is insoluble in dilute hydrochloric acid. Shortly after M.M. Paul Bert and P. Regnard published a memoir upon the action of oxygenated water upon organic matters3 which raised delicate historical questions of chemistry and of physiology and of facts which I could not leave unanswered. This reply was the subject of several notes.4
1. See on these subjects "Les Microzymas," pp. 233-258 and J. Bechamp's "Nouvelles Recherches sur les albumines Normales et pathologiques," p. 93. 2. C. R., Vol. XCIV, p. 1276. 3. C. R., Vol. XCIV, p. 1333. 4. ib., p. 1601, etc.
In the communication of M.M. Bert and Regnard, I had chiefly addressed myself to the following assertion: "That the blood even defibrinated, acted with great intensity upon oxygenated water and that this action seemed to be entirely contained in the serum; and, further, that ossein very clearly decomposes oxygenated water."
I observed also that the authors did not distinguish between the expressions organic matters and animal matters, —which was in conformity with the then state of science. But I knew what to believe regarding the fact that defibrinated blood decomposes oxygenated water, and I had ascertained the nature of the proximate principle which was its agent.
And first let us place it beyond doubt that it is not the serum which, in defibrinated blood, has the greatest share in this decomposition. The fresh yellow (citron) serum which is first pressed out of the clot unquestionably sets free oxygen from the oxygenated water, which might be due to morsels of fibrin remaining in suspension. But the same serum, filtered several times upon a filter lined with sulphate of baryta, acts less and less on the oxygenated water without ever entirely ceasing to do so, which is very simply explained by the secretion in the serum of the substance which, in the fibrinous microzymas, effects the decomposition; but when the serum begins to be red-colored the action upon oxygenated water is incomparably more energetic, the explanation whereof is as follows:
The defibrinated blood contains the red globules, and these contain the red colouring matter and their own (special) microzymas. Much has been written upon this red matter which has come to be called haemoglobin; and which was at first regarded as being a mixture of a colourless albuminoid matter called globulin and of haematosin. Much has also been written upon haemoglobin up to maintaining that it is not an albuminoid because it contains iron. It was J. B. Dumas who first studied and analyzed the colouring matter of the blood of the globules as an albuminoid proximate principle.
I have studied haemoglobin from the same point of view as other albuminoid matters; admitting that it exists combined with potash in the globules, I have succeeded in combining it with the oxide of lead under the form of haemoglobinate. But the haemoglobinate of lead, decomposed by carbonic acid, furnishes soluble haemoglobin in the state of an absolute proximate principle.1
1. C. R., Vol. LXXVIII, p. 850 (1874), and "Memoire sur les Matieres albuminoides," p. 270.
The solution of pure haemoglobin is coagulable by heat and by alcohol; in both cases the coagulum is absolutely insoluble in water. The solution is of deep red colour, the alcoholic coagulum is of a brick red.
Haemoglobin, even coagulated by alcohol, decomposes in the presence of alcoholized ether under the influence of sulphuric acid, into haematosin and a colourless albuminoid matter.
That settled, and to be more precise, and apropos to the communication of M.M. Bert and Regnard, let us recall that Thenard admitted that the action of organic tissues upon oxygenated water was of the same order as that of platinum, etc. Nevertheless he did not fail to point out that while these metals decompose, "an infinite quantity" of oxygenated water, it was not the same with organic tissues and fibrin, some decomposing it for a long time, others for a shorter period. In the first category he placed the tissues of the lung, the liver, the spleen and fibrin newly extracted from the blood; in the second he placed the nails, the fibro-cartilage of the ribs, the tendons, the skin; these, said he, "soon entirely ceased to act," and, much surprised, Thenard sought an explanation of these differences. We will presently learn that the differences pointed out by the illustrious observer related to the different nature of the microzymas of the tissues; meanwhile I will only remark that the most active organic tissues belong to the vascular and respiratory systems. But we must not forget that Thenard took fibrin for an isolated animal matter: that is to say, for a proximate principle of animal origin. Let us then compare the action of fibrin in this respect with that of haemoglobin, which is really an animal proximate principle.
To illustrate: let us take, suppose, 30 grammes of fresh moist fibrin and 6 grammes of fresh moist fibrinous microzymas. In 48 hours the 30 grammes of fibrin will have set free 1,600 c.c. of oxygen from 180 c.c. of water oxygenated to 10.5 volumes of oxygen; that is, 53 c.c. of oxygen per gramme of fresh fibrin or 0.193 grammes dried at 100° C.
In 48 hours the 6 grammes of fibrinous microzymas will have set free 1,000 c.c. of oxygen from 160 c.c. of water oxygenated to 10 volumes of oxygen—i.e., 166 c.c. of oxygen per gramme of moist microzymas or 0.139 gramme, dried at 100° C.
Now as to the haemoglobin. In one experiment 10 c.c. of a solution of this substance, pure, containing 0.338 gramme of matter and 4 c.c. of water oxygenated to 10.5 volumes of oxygen, have set free 30 c.c. of gas in three-quarters of an hour and 34 c.c. in 24 hours. Further, so soon as the disengagement of the gas began, the liquor became cloudy, flocculent matter appeared, and at the end the discoloration was complete. The phenomenon then is correlative to a change and an oxydation, for the oxygenated water being able to set free 42 c.c. of oxygen had only set free 34 c.c. of it; the oxygenated water is, further, almost completely decomposed. If one operates with sufficiently large quantities, heat is developed and carbonic acid mixed with oxygen is set free. As to the other products of the discoloration by oxydation of the haemoglobin they are numerous, and among them albuminoid and other soluble products, and at the same time an insoluble body containing iron. Haemoglobin then, a proximate principle, decomposes oxygenated water, becoming changed in so doing like fibrin and its microzymas; but at equal weights the haemoglobin produces a less disengagement of oxygen than they.
That which distinguishes the mode of being of the haemoglobin is that, even coagulated by alcohol and then heated to 120° C. (= 248° F.), it becomes still more discolored in decomposing oxygenated water, with disengagement of oxygen, while cooked fibrin becomes inactive.
But the haemoglobin is reducible into a colorless albuminoid matter and into haematosin; that is to say, into two new proximate principles. Now the colorless albuminoid matter of the decomposition, freed from the sulphuric acid with which it had been combined, does not set free oxygen from oxygenated water. On the other hand, the insoluble haematosin and oxygenated water react strongly with disengagement of heat and of oxygen mixed with carbonic acid, while, absorbing a part of the oxygen, it is entirely transformed into soluble products. And, what is quite the opposite of what happens with fibrin and fibrinous microzymas, free sulphuric acid does not hamper the reaction.
It is evident from this that the haemoglobin owes lo the ferruginous molecule of haematosin, which is one of the constituent molecules of its own molecule, the property of decomposing oxygenated water, destroying itself by oxydation. And it is thus that certain proximate principles of the fibrinous microzymas and the oxygenated water react, causing the decomposition of the latter with disengagement of oxygen.
Here then are many undisputed proximate principles which act upon oxygenated water after the manner of the organic tissues of which Thenard spoke, and after the manner of fibrin, which is also an organic tissue. It is useful to connect the facts relative to haemoglobin and to haematosin with the reciprocal reaction of hydrocyanic acid and of oxygenated water, to show that they are not isolated facts. Further, Thenard himself observed that oxygenated water of a certain concentration reacted upon cane sugar with disengagement of oxygen and of carbonic acid.
In defibrinated blood it is then especially the haemoglobin of the blood globules which is the agent of the decomposition of oxygenated water; and if the lemon-colored serum (always with little intensity) effects this decomposition, it is because it contains, besides its own albumen, some proximate principle, zymas or other, which is able to do so. In fact the albumen of the serum,1 isolated and pure, is as little endowed with this property as is the white of egg and the colorless albuminoid of the decomposition of haemoglobin.
1. The albumen of the serum! The rotatory power of this albumen has been given in the foregoing table to distinguish it from the albuminoid substances which Bouchardat confounded under the name of albuminose. But its specification is of such importance for an exact knowledge of the blood that it would have deserved a chapter to itself; but thanks to what has preceded, this note will suffice. First, let us remember that Denis (of Commercy) (1856) supposed that the plasmin of the plasma was decomposed, after the bleeding, into concrete fibrin and dissolved fibrin, afterwards called metalbumen. So that, according to this hypothesis, the serum expelled from the clot contains this metalbumen and its own albumin. Denis thought he could verify this hypothesis by isolating from the serum its dissolved fibrin or metalbumen in the following manner: when crystals of a sulphate of magnesia are added to the serum, this salt is dissolved in it and a time comes when the serum is so saturated that no more will be dissolved and a precipitate is formed. It was the substance of this precipitate, insoluble in a saturated solution of sulphate of magnesia—but soluble in water, which was supposed to be dissolved fibrin. One was the more sure of it because, under like conditions, the white of egg. common albumen, gives no precipitate to sulphate of magnesia. Such is the experiment which led to the admission of plasmine and its reduction which would give the metalbumen, which would dissolve in the serum with its own albumen, supposed to be identical with the albumen of while of eggs. But all this is erroneous. The blood contains no plasmin and the serum does not contain two albumins whereof one is metalbumen. In fact, Prof. J. Bechamp, in his "Albumines normales et pathologiques," p. 31, has demonstrated that the precipitate determined in the serum by sulphate of magnesia is the same substance, endowed with the same rotatory power as the serum albumin mentioned in table. Further he proved that certain albumins of the bird's egg are likewise precipitated by sulphate of magnesia, as is known to be the case with certain pathological serosities, but the precipitates thus obtained from these pathological albuminous liquids, also called metalbumens, possess different rotatory powers than those of the albumens of the white of egg of certain birds. Whence the conclusion that there is not a melalbumine or dissolved fibrine. Further the specification does not rest only on the difference in rotatory powers, but on all the properties taken together. But a direct proof will be given that there is nothing in the blood resembling the hypothetical body called plasmin.
This colorless albuminoid of the decomposition of the haemoglobin, by its rotatory power and other properties, is absolutely distinct from the albumins and albuminoids of the table. But the blood globules also contain microzymas which decompose oxygenated water. In studying them it is necessary to observe that the organic tissues which effect this decomposition owe this power especially to their anatomical elements or to some proximate principle secreted by them. In other words, the property of decomposing oxygenated water does not characterize organic tissues or bodies, as was believed by Thenard.
The study of these albuminoids in general, and especially of those of the blood, proves that the nitrogenous inter-microzymian matter of the fibrin is of a special nature, distinct from all other albuminoid matters, especially from the type of albumin which may be coagulated, and that is itself coagulable by heat, becoming thus absolutely insoluble in very dilute hydrochloric acid.1
But the special study of the fibrin which revealed the fibrinous microzymas has taught us nothing with regard tcr the condition of the fibrin in the blood during life, that is to say nothing regarding the relation of the intermicrozymian matter and the microzymas. This will be the subject of the next chapter.
1. To explain how fibrin in its spontaneous changes may give birth to a great number of products of decomposition, it is well to add the following to what I have said as to the complexity of the albuminoid molecule. It is commonly said that albuminoid matter is a nitrogenous quaternary. But I have shown that casein, absolutely free from mineral matter, contains phosphorus, and as the casein in the mammary gland results from the transformation of the albuminoid matters of the blood, it follows that these are also phosphoretted; casein also contains sulphur, which was known, but was supposed to be accidental. Then the haemoglobin contained iron. An albuminoid molecule may thus contain besides carbon, hydrogen, nitrogen and oxygen, phosphorus, iron and sulphur, seven elements instead of four. I have observed that in the albuminoid matters of the vitellin microzymas the sulphur does not produce sulphuric acid precipitable by baryta when they are oxydized by the hypermanganate of potash; in this it resembles Taurine, "Memoire sur les matieres albuminoides," p. 389.
