COMPOSITION OF FIBRINE &c. 



41 



most beautiful and interesting observations 

 on the action of empyreumatic substances, 

 such as wood, vinegar, creosote, &c., on 

 malignant wounds and ulcers. In such 

 morbid phenomena two actions are going 

 on together; one metamorphosis, which 

 strives to complete itself under the influence 

 of the vital force, and another, independent 

 of that force. The latter is a chemical pro- 

 cess, which is entirely suppressed or arrested 

 by empyreumatic substances ; and this effect 

 is precisely opposed to the poisonous influ- 

 ence exercised on the organism by putrefy- 

 ing blood when introduced into a fresh 

 wound. 



14. The formula C H* N 6 O M * is that 

 which most accurately expresses the com- 

 position of proteine, or the relative propor- 

 tions of the organic elements in the blood, 

 as ascertained ty analysis. Albumen, fibrine, 

 and caseine contain proteine; caseine con- 

 tains, besides, sulphur, but no phosphorus ; 

 albumen and fibrine contain both these sub- 

 stances chemically combined the former 

 more sulphur than the latter. We cannot 

 directly ascertain in what form the phos- 

 phorus exists. But we have decided proof 

 that the sulphur cannot be in the oxidized 

 state. All these substances, when heated 

 with a moderately strong solution of potash, 

 yield the sulphur which we find in the solu- 

 tion as sulphuret of potassium ; and on the 

 addition of an acid it is given off as sul- 

 phuretted hydrogen. When pure fibrine or 

 ordinary albumen is dissolved in a weak 

 solution of potash, and acetate of lead is 

 added to the solution, in such proportion 

 that the whole of the oxide of lead remains 

 dissolved in the potash, the mixture, if 

 heated to the boiling point, becomes black 

 like ink, and sulphuret of lead is deposited 

 as a fine black powder. 



It is extremely .probable, that by the 

 action of the alkali the sulphur is removed 

 as sulphuretted hydrogen, the phosphorus 

 as phosphoric or phosphorus acid. Since, 

 in mis case, sulphur and phosphorus are 

 eliminated on the one hand, and oxygen and 

 hydrogen on the other, it might be con- 

 cluded that fibrine and albumen, when 

 analyzed with their sulphur and phosphorus, 

 would yield a larger proportion of oxygen 

 and hydrogen than is found in proteine. But 

 this cannot be shown in the analysis; for 

 fibrine, for example, has been found to con- 

 tain 0'3G per cent, of sulphur. Assuming, 

 then, that this sulphur is eliminated by the 

 alKali in combination with hydrogen, pro- 

 teine would yield 0-0225 per cent, less hy- 

 drogen than fibrine; instead of the mean 

 amount of 7-062 per cent, of hydrogen, the 

 proteine should yield 7*04 per cent. In like 

 manner, by the elimination of the phos- 

 phorus in combination with oxygen, the 

 amount of oxygen in fibrine would be re- 

 duced from 22-715 22-00 per cent, to 22- 5 



* For the method of converting this and other 

 formula into propoitions per cent., see Appendix. 



21 '8 per cent, in proteine. But the limits of 

 error in our analyses are, on an average, 

 beyond y^th per cent, in the hydrogen, and 

 beyond T * 5 ths per cent, in the oxygen ; while 

 in the supposed case the difference in the 

 hydrogen would not be greater than ^th 

 per cent. 



Finally, if we reflect, thai the elimination 

 of oxygen and hydrogen with the sulphur 

 and phosphorus does not exclude the addi- 

 tion of the elements of water, and if we as- 

 sume that fibrine and albumen, in passing 

 into proteine, do combine with a certain 

 quantity of water, an occurrence which is 

 highly probable, we shall see that there is 

 no probability that the ultimate analysis of 

 these compounds shall ever enable us to de- 

 cide such questions, or to fix the chemical 

 view of the relation of proteine to albumen, 

 fibrine, or caseine, farther than has been 

 done above. 



Some have endeavoured to prove the ex- 

 istence of unoxidized phosphorus in albumen 

 and fibrine from the formation of sulphuret 

 of potassium when they are acted on by 

 potash, supposing the oxygen of the potash 

 to have formed phosphoric acid with the 

 phosphorus; but caseine, which contains 

 no phosphorus, yields sulphuret of potas- 

 sium, just like the other substances; and 

 here its formation cannot be accounted for, 

 unless we admit the previous production of 

 sulphuretted hydrogen. In the mere boiling 

 of flesh, for the purpose of making soup, 

 sulphuretted hydrogen, as Chevreul has 

 shown, is disengaged. 



Moreover, the proportion of sulphur, foi 

 the same amount of phosphorus, is not the 

 same in fibrine and albumen, from which no 

 other conclusion can be drawn, but that the 

 formation of sulphuret of potassium has no 

 relation to the presence of phosphorus. Sul- 

 phuret of potassium is formed from caseine, 

 which is not supposed to contain any un- 

 combined phosphorus; and it is formed, 

 also, from albumen, which contains only 

 half as much phosphorus as fibrine. 



Every attempt to give the true absolute 

 amount of the atoms in fibrine and albumen 

 in a rational formula, in which the sulphur 

 and phosphorus are taken, not in fractions, 

 but in entire equivalents, must be fruitless, 

 because we are absolutely unable to deter- 

 mine with perfect accuracy the exceedingly 

 minute quantities of sulphur and phosphorus 

 in such compounds ; and because a variation 

 in the sulphur or phosphorus, smaller in 

 extent than the usual limit of errors of ob- 

 servation, will affect the number of atoms 

 of carbon, hydrogen, or oxygen to the extpnt 

 of 10 atoms or more. 



We must be careful not to deceive our- 

 selves in our expectations of what chemical 

 analysis can do. We know, with certainty, 

 that the numbers representing the relative 

 proportions of the organic elements are the 

 same in albumen and fibrine, and hence we 

 conclude that they have the same composi- 

 tion. This conclusion is not affected by the 



D* 



