1913] Walter H. Eddy 43 1 



acetic acid and extraction of the purified precipitates with 0.8 per 

 Cent, hydrochloric acid Solution. 



Precipitation (modification of Lilien feld's process) of water 

 extracts with a few drops of conc. hydrochloric acid Solution and 

 extraction of the purified precipitates with 0.8 per cent. hydrochloric 

 acid Solution. 



Acidificationof water extracts [after Kossei and Kutscher (16)] 

 with hydrochloric acid, to 0.8 per cent. strength, and filtering. 



Precipitation of water extracts with alcohol and extraction of 

 the washed precipitates with 0.8 per cent. hydrochloric acid Solution. 



Precipitation of water extracts [after Huiskamp (10)] with 

 calcium chlorid, to 0.2 per cent. strength, and extraction of the 

 purified calcium chlorid-precipitates with 0.8 per cent. hydrochloric 

 acid Solution. 



In every case the ammonia-precipitated product from the histoo 

 hydrochlorid Solution was insoluble in water, and addition of am- 

 monia to the acid Solution gave a precipitate which differed in no 

 respects from that obtained by first removing free acid by dialysis 

 and then precipitating with ammonia. The best precipitation re- 

 sults were obtained by first carefully neutralising the acid Solution 

 with ammonia and then adding the excess a few drops at a time, 

 with stirring. It was demonstrated that ammonia-precipitation 

 takes place in the absence of salts (contrary to Bang's contention), 

 but care must be taken to add the ammonia slowlv and in small 

 amounts. 



The insolubility of the ammonia-precipitated product was shown 

 to be due neither to the action of the alcohol or ether used in wash- 

 ing the product, nor to abnormalities in the glands used. It was 

 found to increase with the length of the period in distilled water. 

 Precipitates allowed to stand for several weeks in distilled water, 

 with toluene, failed to dissolve or putrefy and ultimately became 

 completely insoluble in 0.8 per cent. hydrochloric acid Solution. 



In contrast with these results, the histon obtained by saturating 

 a histon-hydrochlorid Solution with sodium chlorid was invariably 

 soluble in water. This solubility was not altered by washing with 

 alcohol and ether, by drying at 45°, or even when the product was 

 dried to constant weight at 105° C; the sodium chlorid-saturation 

 products from both add and neutral histon-hydrochlorid Solutions 



