246 Some New Constituents of Milk. III 
ment as employed in making preparation B, 59 gm. of preparation 
D were obtained. Preparations A, B, and C represent succes- 
sive fractional precipitations, while D includes all of the protein 
removed by extracting the casein a second time with somewhat 
stronger alcohol. | 
The following analyses show no appreciable differences be- 
tween these several fractions of this peculiar protein. 
Preparation. wie nese eee A B C D 
per cent per cent per cent per cent 
Mogsture ati 110") en. as 9.49 5.99 7.00 8.09 
AST ine Suen i eight eae 1216 0.62 1.73 0.57 
Calculated Ash- and Moisture-Free. 
15.80 15.67 15.70 15.49 
INTUPOGCT ee beet 1ST 15.67 15.70 15760 
15.88 
SBE Ui sels se gene eae eee 0.97 0.94 0.94 1.00 
Phosploris ay wie eee os hice ERIC 0.03 0.10 0.03 
A composite sample of these four preparations was analyzed 
for carbon and hydrogen with the following results, calculated 
moisture- and ash-free. 
Car bOneit . 45.2. aa Wie oe ee ee ee 55 07 54.86 
Hydrocens 0.5 eae ue ele even ee ae ne eee 7.24 1.23 
A fifth preparation of this protein was made from the first 
and second alcoholic washings of another lot of casein which 
had been precipitated from about 500 liters of milk. The pro- 
tein which separated after cooling the concentrated washings 
was dissolved in a little warm 70 per cent alcohol and its solu- 
tion poured into about 50 liters of cold water. On adding so- 
dium chloride most of the protein separated. The precipitate 
was collected on filters, redissolved in warm 70 per cent alco- 
hol, and the solution filtered through paper pulp. The filtrate 
and washings (about 2 liters) were concentrated in vacuo to 
about 800 cc. with sufficiently frequent additions of strong alco- 
hol to keep the protein dissolved. The concentrated solution 
was poured into a large volume of absolute alcohol and the 
resulting precipitate sucked out, washed first with absolute 
alcohol and then with ether. This preparation, E, when dried 
in warm air weighed 112 gm., and had the following composition. 
