400 THE PHOSPHORUS CONTENT OF THE 



concentrated neutralized solutions by the use of alcohol, P 

 (like all the preparations showing low ash content) was first 

 precipitated by means of acid before subsequent treatment 

 with alcohol and ether. 



It seemed reasonable to assume that the high content of ash 

 present in preparations A and D was due to the simultaneous 

 precipitation of relatively insoluble salts, such as calcium salts 

 or more probably to the fact that when the precipitation take; 

 place in a neutralized solution of paranuclein, the latter i 

 carried down in combination with an alkali earth such as cal 

 cium. Since the paranuclein behaves like an acid substance, 

 it is reasonable to suppose that it may enter into loose com- 

 bination with calcium, forming compounds analogous to those 

 of casein with calcium and the alkalies. In this event the large 

 amount of calcium present in the preparation would on ignition 

 tend to hold the phosphorus originally present as organic 

 phosphorus in the form of calcium phosphate in the ash. The 

 discrepancy between the results of Chittenden and other 

 observers would thus be attributable to the fact that he pre- 

 cipitated the paranuclein in combination with calcium or an 

 alkali, and owing to the reaction above described, was led to 

 assume the absence of organic phosphorus in the paranuclein. 

 In order to test still further the validity of this assumption, 

 a portion of the paranuclein with high ash content (preparation 

 D) was redissolved in 1 per cent sodium carbonate solution 

 and reprecipitated with hydrochloric acid. After filtration 

 the precipitate was washed with distilled water until the 

 washings gave no test for chlorides. 



Preparation G. An analysis of this substance after treat- 

 ment with alcohol and ether and drying at 105 C. gave the 

 f ollowing results : 



Ash = 0.66%. 



Total phosphorus = 2.35% . Phosphorus found in ash = 0.0% . 



Phosphorus in substance in organic combination = 2.35%. 



It will be seen that the preparation obtained in this way 

 was an extremely pure product. Thus it is quite possible to 



