New YorK AGRICULTURAL EXPERIMENT STATION. 57 
in aiding the development of body tissues in the young animal. The 
evidence is quite conclusive that certain phosphates are useful in the 
_ former case but the data covering the latter point are conflicting and 
it is still an open question whether calcium phosphates possess 
nutritive value when added to a ration of normal food materials. ° 
Kohler? working with lambs found that calcium and phosphoric 
acid were most thoroughly assimilated in the form of precipitated 
calcium phosphate, which is a mixture of tri- and di-calcium phos- 
phates. Atwater* has shown that the ash constituents of beef are 
largely absorbed from the digestive tract of man. Hoppe-Seyler® 
finds the same to be true of calcium phosphate and the several ex- 
periments of Gohren®, Lehmann’ and Wildt® give similar results 
with small animals. | 
The evidence as to the benefits derived from the use of inorganic 
phosphates when fed to sound animals is contradictory. Cohn? 
reports observations on the addition of calcium phosphate to the 
food of calves and pigs where no apparent influence was exerted, 
while a marked benefit was observed in experiments with two to 
three-year-old horses. Hofmeister? failed to receive beneficial re- 
turns from the use of precipitated calcium phosphate with three- 
months’ old lambs. Heiden?® observed an increased weight and a 
general beneficial influence from the addition of 25 grams of calcium 
phosphate to the daily food of weak pigs, but when stronger animals 
were used no influence was evident. 
Hess and Schaffer!! report that when 50 grams of calcium phos- 
phate was added to the daily food of four cows the milk contained 
an increased proportion of that compound. The experiment 
station at Mockern™ reports most beneficial results from the use 
of 30-50 grams of calcium phosphate in the daily rations of steers 
which had shown marked brittleness of their bones, caused by ad- 
ministering a ration poor in phosphorus. H. Joulie!® reports 
®Ztschr. Untersuch. Nahr, u. Genussmtl., 8:683. 1904. 
*Ztschr. Biol., 24:16. 1888. 
5°Med. Chem. Untersuch., Heft 2. 
*Landw. Vers. Stat., 3:161. 1861. 
*Jahresber. Agr. Chem., 16, Bd. 2: 183, 1876. 
SJour. Landw., 22:1. 1874. 
*Landw. Vers. Stat., 1873, p. 123 
*Jahrsber. Agr. Chem., 16, Bd. 2:62. 1876. 
% Landw. Jahrb. Schweiz, 5:76. I8o1. 
*Landw. Vers. Stat., 57: 230, 1902. 
*® Rev. Agr. Reunion, 10: 1904. 
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