T. B. Osborne and A. J. Wakeman 11 
second injection. On the other hand, those sensitized with a. 
preparation of the carefully purified globulin showed no reaction 
to a subsequent injection of lactalbumin, nor were they protected 
against a later injection of the globulin, for animals thus treated 
died within a few minutes. 
‘Assuming that 1 liter of whole milk, containing 3.5 per cent 
of fat, is equal. to 965 cc. of skimmed milk, the 10.11 gm. of 
ash- and moisture-free coagulated lactalbumin obtained in this 
experiment from 4 liters of skimmed milk are equal to about 2.4 
gm. per liter of the original whole milk. That the actual amount 
of lactalbumin was somewhat greater than this is indicated by 
facts discussed later in this paper in connection with the possible 
presence of proteoses in milk. 
Lactoglobulin. 
In order to remove completely lactalbumin from precipitate 
A (page 9), which was produced by saturating the neutral solu- 
tion with magnesium sulfate, this was dissolved in about 400 ce. 
of water, the solution again saturated with magnesium sulfate, 
and the precipitate filtered out and pressed very thoroughly 
between filter paper. After repeating this process the final 
precipitate, when dissolved in about 250 cc. of water, yielded 
a brownish colored, strongly opalescent, but transparent solu- 
tion which was just perceptibly acid to delicate litmus paper. 
Dropped into much distilled water a cloud formed suggesting 
precipitation, but on mixing only a turbidity remained. When 
3 cc. of this solution were mixed with 3 cc. of water 4 or 5 drops: 
of 1 per cent acetic acid and 0.5 cc. of 20 per cent sodium chloride 
solution, a coagulum appeared on heating to 71°, which sepa- 
rated in much finer flocks than those yielded by heating a solution 
of lactalbumin. After heating at 71-75° for a short time the 
coagulum was filtered out. The filtrate gave no turbidity on 
boiling but did give a slight precipitate when saturated with 
ammoniym sulfate. 
The main solution was accordingly diluted with water to 
600 cc., made distinctly acid to litmus with 3 cc. of 1 per cent 
acetic acid, and 30 cc. of a 20 per cent sodium chloride solution 
were added, which caused opacity in thin layers, but produced 
