Muscular and Pulmonary Tissues, 363 



ing to pyrophosphate of potash, which may be originally the 

 neutral tribasic phosphate of potash subsequently decomposed by 

 incineration. It will be observed that these four analyses all 

 yield a similar result, which will be found confirmed by the 

 composition of the human muscles subjected to analysis*. 

 This result is the discovery of the existence of phosphoric 

 acid and potash in the effete material exactly in the right 

 proportion for the formation o^ pyrophosphate of potash. 



I believe this is the first time the composition of an inor- 

 ganic chemical compound has thus been determined by bringing 

 together, theoretically, its constituents in an animal tissue. The 

 formation of this substance is very remarkable; it shows be- 

 yond a doubt that blood yields (besides albumen, phosphoric acid, 

 and small quantities of potash and magnesia to be transformed 

 into flesh) a large proportion of potash the only object of which 

 is the removal of the phosphoric acid of the ripe muscular tissue. 

 Potash may also be concerned in the oxidation of the albumi- 

 nous portion of the tissue into crystalloid compounds ; and I 

 may remind the reader that Dr. E. A. Parkes has shown that 

 potash taken into the body favours oxidation, causing an in- 

 creased elimination of urea and sulphuric acid. 



The proportions of the constituents of flesh I have introduced 

 under class No. 3 are originally derived from the composition 

 of the extract, from which are subtracted respectively the propor- 

 tions of the colloid substances present. These colloid consti- 

 tuents are calculated from the composition of the insoluble 

 fibrous portion of the tissue and the proportion of the soluble 

 albumen ; so that any error in any one of the determinations of 

 albumen, phosphoric acid, or potash would suffice to vitiate the 

 whole of the result. 



Absence of Soda and Chlorine from ripe Muscular Tissue, or the 

 insoluble portion of flesh. 



The proportions of chlorine and soda contained in juice of 

 flesh are very small ; in eleven analyses of the extracts from 

 the flesh of as many different animals, the proportions of chlorine 

 in 200 grammes varied from 0094 to 0*212. These results may 

 be considered correct, notwithstanding their being represented 



* The proportions of phosphoric acid and potash effete in human mus- 

 cular tissue after death from phthisis were as follows in three analyses : — 



Analysis T. II. III. Mean. 



Phosphoric acid 432 429 427 429 



Potash 56-8 57'1 dJS 57-1 



