New YorkK AGRICULTURAL EXPERIMENT STATION. 161 
The results embodied in Tables III and IV are summarized 
as follows: 
(1) The formation of water-soluble and salt-soluble nitrogen, 
together with the conversion of lactose into lactic acid, as shown 
in Table III, proceeds in general as in the preceding experi- 
ments. i1t will be noticed, however, that we failed to get a 
sample of cheese for analysis when the salt-soluble nitrogen was 
as high as in the preceding experiments. Apparently, between 
7% hours and 24 hours, very little change had taken place in 
the amount of salt-soluble nitrogen; but, according to results 
with other cheeses, there is reason to believe that, during this 
interval, the salt-soluble nitrogen increased until the nitrogen all 
became salt-soluble and then began to change into the succeed- 
ing form, which is insoluble in salt solution, and at the end of 
24 hours had decreased nearly to the point at which the salt- 
soluble stood at the end of 7% hours. 
(2) The amount of calcium compounds found in the water- 
extract increases quite rapidly for a few hours and then more 
slowly, reaching a maximum in about 2 weeks, when about 
80 per ct. of the calcium compounds in the cheese is found in 
the water-extract of the cheese. After this the amount of water- 
soluble calcium compountls appears to remain about constant. 
The water-soluble calcium appears to represent, in the main, 
two compounds, (1) mono-calcium phosphate and (2) calcium 
lactate. The results.suggest that about 20 per ct. of the cal- 
cium in cheese is not given up to a water solution, either being 
held mechanically by the proteid or else existing in combination. 
It hardly seems probable that this calcium is there as insoluble 
calcium phosphates so long as enough lactic acid is formed to 
change it all into mono-calcium phosphate. It appears more 
likely that it is in combination with paracasein, as will be 
shown later. 
(3) The amount of water-soluble P,O,; increases rapidly for 
the first few hours and then continues gradually to increase until 
finally all the inorganic phosphorus compounds appear in the 
water-extract. This indicates that enough lactic acid has been 
formed to convert the insoluble calcium phosphates entirely into 
mono-calcium phosphate with simultaneous production of cal- 
Cinmimiactate.-.. 
(4) The amount of calcium lactate increases rapidly in the 
first few hours. 
6 
