PHOSPHATE OF LIME. 415 



blood into these tissues its protein -compounds part with the soluble 

 phosphate of soda but retain a large quantity of the phosphate of 

 lime. It is thus that Liebig accounts for the special power which 

 hydrochloric acid possesses of dissolving these substances during 

 the process of digestion. 



Well dried muscular fibre contains, according to von Bibra, 

 from 0-938 to 1'OOSf of bone-earth. 



Phosphate of lime is found in solution in all the animal fluids ; 

 its presence has long been recognised in the blood, the urine, 

 the fluids of serous membranes, the saliva, gastric juice, milk, 

 and seminal fluid, but it was for a long time unknown by what 

 means this insoluble body was retained in solution in alkaline and 

 neutral fluids. As a general rule phosphate of lime is chemically 

 combined wtih the protein-compounds and similar organic matters, 

 and is retained by them in their solutions as well as in their meta- 

 morphoses into the tissues. Moreover it has been long demonstrated 

 by Berzelius and Thenard, that phosphate of lime is to a certain 

 degree soluble in fluids containing much carbonic acid; we know 

 from analytical chemistry, that it is not altogether insoluble in 

 fluids containing hydrochlorate of ammonia, and recently Liebig 

 has shown that a little phosphate of lime is taken up by solutions 

 of chloride of sodium. The solubility of bone-earth in animal 

 fluids is thus sufficiently intelligible. 



We have already spoken of the solvent power which lactic acid 

 exerts on phosphate of lime. In opposition to the experiments of 

 Walter Crumf I will only remark that in my experiments (taking 

 the mean of six) 68*55 parts of basic phosphate of lime were 

 dissolved by 100 parts of anhydrous lactic acid, while a fluid 

 containing 100 parts of anhydrous acetic acid could only dissolve 

 17'49 parts of the same salt. 



The ash of the protein-compounds consists for the most part of 

 phosphate of lime; BerzeliusJ found 1'8-g- in the albumen from the 

 serum of ox-blood, while Mulder found 2'03& and Marchand from 

 2-1 to 2 -5 in that of the egg; in soluble albumen precipitated by 

 great dilution and neutralisation, I found l"3% of phosphate of lime ; 

 in well-washed fibrin from the venous blood of a man, I found only 

 0-694^. Casein, globulin, chondrin, and glutin also contain phos- 

 phate of lime as an integral constituent. Casein, according to Mul- 

 der contains 6$ of phosphate of lime, which, when the casein is coag- 



* Ann. de Ch. u. Pharm. Bd. 61, S. 128. 



t Ibid. Bd. 63, S. 394 ff. 



J Lehrb. d. Ch. Bd. 9,8.35. 



Arcliiv. f. 1828, p. 155. 



