Julia T. Emerson and William H. Welker 343 



washed. Sometimes the bark was removed; at other times the 

 entire root, after removal of injured or abnormal portions, was 

 finely divided in a meat chopper. Portions of the chopped tuber 

 were at once put in bottles with one of the solvents named below, 

 a few drops of toluol or chloroform being added as preservatives. 

 After standing generally a week, the extract was filtered and this 

 filtrate used in the experiments. 



Extracts were made with the following solvents: Water, 95 

 per cent alcohol, ether, glycerol, 10 per cent sodium chlorid, or 

 acidified water (very dilute hydrochloric acid). The aqueous 

 and saline extracts were slightly acid in reaction (litmus). 



The common qualitative reactions on these extracts made it 

 evident that the root contains representatives of the following 

 groups of substances: proteins, carbohydrates, fats, cholesterins, 

 lecithins, basic substances, salts of organic acids, and inorganic 

 salts. 



Proteins. The simple proteins present in the tuber were of the 

 coagulable type only. Proteose and peptone could not be de- 

 tected in any of the extracts after removal of the coagulable pro- 

 teins. Nucleoprotein was present in small proportions in the 

 extracts and could be precipitated by acid. On decomposition 

 in hot acid the protein yielded purin bases, simple protein and 

 phosphate. 



It was hoped by finding the temperature at which coagulations 

 resulted in the extracts, to gain some idea of the number and 

 types of the coagulable proteins present. The results were not 

 very definite, however. Ten per cent salt extract, for example, 

 showed turbidity at the low point of 25° C. The temperature 

 was gradually raised and at 61° C. a fine flocculent precipitate 

 appeared. On filtering, a clear yellow filtrate was obtained. 

 On reheating, initial turbidity became apparent above the tem- 

 perature of former turbidity but below that of former flocculation ; 

 in this way six to eight flocculations were obtained at tempera- 

 tures ranging between 25° C. and 80° C. 



On adding to an aqueous or saline extract an equal volume of 

 saturated ammonium sulfate solution, a fairly bulky precipitate 

 of "globulin" was obtained. The half saturated filtrate gave an 

 abundant yield of albumin when ammonium sulfate was added 

 to complete saturation. Saturation of the saline extract with 



