166 H. S. H. WARDLAW. 
the substance ashed in the muffle in the usual way; the 
second result was obtained after destroying the organic 
matter with concentrated nitric and sulphuric acids (Neu- 
mann’s (1902) acid-ashing process.) 
Deposit from Milk 51. 
Weight of Deposit.| Wt. of Mg,P,0, | Percent. of P,O, 
Dry ash «4° 0°2527 em, 0:0146 gm. 3°68 
Acid “ash 21), 7019700 | 0-012 3°91 
These figures show a loss of phosphorus of about 6% dur- 
ing the ignition. This value is not much greater than the 
experimental error on the estimation of such small quan- 
tities of phosphorus as had to be dealt with in these cases. 
5. Amount of Nitrogenous and Non-nitrogenous Organic 
Matter in the Deposit. 
The ash-content of the deposit obtained from milk by 
spinning it ina centrifuge shows that there is present about 
92°/ of material which disappears on ignition. The amounts 
of nitrogen in a series of these deposits have been deter- 
mined by the method of Kjeldahl. The following are the 
results obtained :— 
Table VITI. 
Nitrogen-content of Deposit. 
Deposit. Percentage of Nitrogen. 
17 Li8 
25 10°7 
35 10°95 
36 11295 
ate | 12-05 
The average percentage of nitrogen in these deposits is 
therefore 11°5. This corresponds to a percentage of protein 
of 72'8 (taking the nitrogen-content of the protein as 15°87). 
On being allowed to stand for a day or two in the moist 
state these deposits set to a firm clot and developed a 
‘“‘cheesy’’? smell. <A flocculent precipitate was formed 
