New YorK AGRICULTURAL EXPERIMENT STATION. 245 
containing only .042 per ct. of ash. This preparation was still 
slightly soluble in warm salt solution and in hot 50 per ct. alcohol. 
Behavior of casein preparation toward calcium carbonate.—We 
rubbed in a mortar .5 gram of the casein preparation described 
above with finely divided calcium carbonate, suspended in water. 
The mixture was filtered several times through paper, giving a 
slightly opalescent filtrate. This solution was precipitated by 95 
per ct. alcohol, the precipitate was washed several times with 
alcohol, then treated with ether and dried at 100° ©. This prepa- 
ration contained 2.46 per ct. of CaO, agreeing very closely with 
Séldner’s work in which he showed by an indirect method that 
a cisein preparation treated with calcium carbonate combined 
with 2.39 per ct. of CaO. A part of this calcium casein pre- 
paration was dissolved in dilute ammonia, reprecipitated by 
dilute acetic acid and the precipitate, after thorough washing and 
filtering, was again obtained practically ash-free. 
Solubility of casein preparation in lime-water.—We dissolved 3 
grams of the casein preparation in lime-water and obtained an 
opalescent solution. 
Preparation of basic calcium casein.—The lime-water solution of 
casein was made neutral to plenolphthalein by ;, hydrochloric 
acid and became somewhat more milky. This solution, neutral to 
phenolphthalein, was treated with 95 per ct. alcohol, and the 
resulting precipitate, which readily separated, was washed 
several times with alcohol, finally with ether and dried at 100° C. 
This precipitate contained calcium chloride, either as the result 
of occlusion or possibly of a loose combination with the proteid. 
In several preparations made, calcium chloride was always pres- 
ent in amounts varying from .75 to 1.2 per ct. Chlorine and 
calcium oxide determinations were made with the following re- 
sults: 1.24 grams of material yielded .0331 gram of CaO. 
There was present .0063 gram of Cl, equivalent to .0097 gram of 
CaCl,.or .0047 gram of CaO. This would leave .0284 gram of 
CaO combined with casein, or 2.29 per ct. This preparation was 
therefore the basic calcium casein of Soldner. It was insoluble 
in 5 per ct. salt solution and in hot 50 per ct. alcohol. 
Preparation of neutral calciwn casem.—When a solution of 
casein in lime-water is made neutral to phenolphthalein, the 
basic calcium casein is formed, containing 2.29 to 2.46 per ct. of 
