K. OSHIiMA AND M. AKIIZUMI. 
Isolation of Creatinin as Creatinin Zinc Chloride. 
If the solution under examination contains compounds ^"ivin^- similar 
color reactions as Creatinin, the color reaction alone can not be depended 
upon as the criterium for the presence of Creatinin in it. Hence, when 
the indications for the presence of Creatinin were obtained by the color 
tests, it was confirmed and established by the preparation of the characte- 
ristic crystals of Creatinin zinc chloride. Creatinin zinc chloride forms 
prisms or slender needles, grouped in rosettes, clusters and stars. The 
crystal is formed when concentrated solutions of Creatinin and of zinc 
chloride are mixed in the absence of free mineral acids, a condition usually 
obtained by the addition of a little sodium acetate. When a large cjuantity 
of Creatinin is treated in the manner above described there is immediate 
precipitation, but when small quantities are being treated, the precipitation 
does not begin for several hours and not complete for se\ eral days. The 
time required for crystal-formation seems also to be greatly influenced 
b}' the amount of impurities present in the syrup. 
A. From impure syrup. 
To the syrup II the solution of sodium acetate and of zinc chloride 
were added and the mixtin^e ^\'as kept in a desiccator over concentrated 
sulphuric acid. Gradually the solution became concentrated and the forma- 
tion of characteristic crystals of Creatinin zinc chloride Avas observed, 
but not in all cases. The time required for crystal-formation, the forms 
of crystals etc. are described in the following. 
Adzuki bean. The characteristic crystals appeared after lo days in 
the forms of stars, crossed needles and clusters, and after i6 days they 
grew larger and well de\eloped monoclinic plates were obserbed. 
Black soy bean. Crystals were not observed. 
Yellow soy bean. 
Kidney bean. The characteristic crystals appeared after about 3 
weeks. They were radiated needles or crosses. 
Green peas. The characteristic crystals appeared after about 10 
days. Crystal forms were the same as in the case of kidnc}' bean. 
