Society of Biological Chemists Nab: 
veloped almost indefinitely, but high concentrations of carbonate 
lead to the occurrence of secondary reactions, so that the color 
developed is again not directly proportional to the concentration 
of sugar. Thus the concentration of carbonate cannot be in- 
creased to cause the reaction to go to completion in dilute solu- 
tion. It was found, however, that in high concentration of 
picric acid (greater than a saturated aqueous solution) the reac- 
tion with glucose will be definite and quantitative in dilute solu- 
tion in the presence of a moderate concentration of sodium car- 
bonate. Details of the method thus developed will be published 
shortly. - 
A PRELIMINARY REPORT ON THE URINARY EXCRETION OF 
SUGAR IN THE NORMAL DOG. 
By STANLEY R. BENEDICT ann EMIL OSTERBERG. 
(From Department of Chemistry, Cornell Medical College, New York City.) 
The excretion of sugar in the urine of a normal dog upon vari- 
ous diets was studied by means of a new method for determination 
of sugar in normal urine. The technique will be published in 
detail shortly. The results of the study showed that sugar ex- 
cretion in the normal dog bears no relation to urinary volume, 
but is dependent upon food ingestion and the nature of the diet. 
After food is eaten the curve of sugar excretion promptly rises, 
reaching a maximum usually in the 4th to 5th hour after the feed- 
ing. The curve then falls quite rapidly, reaching a low level 
during the early morning hours. The sugar excretion is less on a 
meat diet than on a diet rich in starch, but the curve of sugar 
excretion follows the same general curve in both cases. 
A NEW FORM OF COLORIMETER. 
By JOSEPH C. BOCK ann STANLEY R. BENEDICT. 
(From Department of Chemistry, Cornell Medical College, New York City.) 
An accurate colorimeter has been developed in which the place 
of costly and difficultly obtainable prisms is taken by mirrors. 
The instrument will be described in detail later. 
