THE PHOSPHATES. 225 



acid phosphates in them, although striking and inexplicable, is yet 

 not inconceivable. After the wonderful discoveries of Graham in 

 reference to these complicated endosmotic phenomena, which have 

 hitherto been so imperfectly reduced to definite laws, we need no 

 longer be surprised when we see an acid fluid separating from 

 the alkaline blood, or an acid phosphate separating from the neutral 

 phosphate, and permeating the coats of the vessels. A similar 

 view must be taken of the faintly acid or neutral fluids in which, 

 at all events at present, no organic acid has been recognised, as for 

 instance, the yolk and the contents of the blood-cells ; for it is cer- 

 tainly not very probable that these adjuncts, or faintly acid bodies, 

 such as casein or glycerine, should be capable of decomposing the 

 neutral alkaline phosphate. 



We must here refer to an observation which is intimately con- 

 nected with the above-described facts, and which bears upon the 

 influence of these unknown laws, of diffusion and endosmosis ; we 

 allude to the fact first observed by Liebig during his investigation 

 of the muscular fluid, and subsequently confirmed by C. Schmidt 

 in his investigation of the contents of the blood-corpuscles, namely, 

 that these fluids, which are so rich in phosphates, and which exhibit 

 an acid reaction, contain only a small amount of soda-salts and 

 alkaline chlorides, while they are very rich in potash. This observa- 

 tion I have been able to confirm (see pp. 71 an d 87) in examining 

 the parenchymatous juice of the different contractile tissues ; for I 

 found that acid sweat, which was almost entirely free from phos- 

 phoric acid, contained a much larger quantity of potash-salts than 

 were contained in the alkaline animal juices, which were richer in 

 phosphoric acid. The experiments hitherto made on endosmosis 

 and diffusion have indeed afforded some indications of the readiness 

 with which the potassium-compounds transude, although they 

 have not yielded any more precise results ; Graham's* most recent 

 experiments have merely demonstrated that hydrated soda and 

 the soda-salts in general are diffused somewhat more strongly than 

 hydrated potash, and the corresponding potash- salt. Here again, 

 therefore, we are deficient in the elements necessary to furnish an 

 explanation of these phenomena ; that is to say, we are ignorant of 

 the physical laws, whose application to organic nature, and whose 

 utility in proving that all vital phenomena are results of a physical 

 necessity, constitute the true essence and the ultimate aim of phy- 

 siological chemistry and physiology. As long, therefore, as we 

 continue in ignorance of the leading physical premises, we should 



* Chemical Gazette. 1851, pp. 256-258. 

 VOL. III. Q 



