120 
Scientific Proceedings (44). 
into metabolism by the oxidation of the food is neutralized by 
ammonia in man, an experiment was made in which the influence 
upon ammonia excretion of a known change in the diet was studied 
quantitatively. The change of food consisted in substituting rice 
for potatoes in a simple mixed diet and (neglecting the feces but 
allowing for the unoxidized sulphur excreted during each period) 
was calculated as equivalent to the introduction of 28.3 c.c. normal 
acid per day. The increased ammonia excretion was equivalent 
to 10.7 c.c. normal acid per day. Thus, only about one third of 
the extra acid introduced by the change of food was eliminated 
as ammonia salt. 
The authors take pleasure in acknowledging their indebtedness 
to Professor Mandel for the privilege of carrying on a part of the 
work in his laboratory at the University and Bellevue Hospital 
Medical College. 
72 (597) 
The determination of small amounts of iodine in organic 
combination — A modification of Hunter's method. 
By E. 0. KENDALL. 
[From the Pathological Department of St. Luke's Hospital, 
New York j F. C. Wood, Director.] 
Hunter's method for the determination of iodine in organic 
combination consists of fusion of the organic matter, and the 
formation of sodium or potassium iodide. The iodide is oxidized 
to iodate with sodium hypochlorite, phosphoric acid is added, and 
the excess of chlorine is removed from solution by boiling. Potas- 
sium iodide is now added and each molecule of iodate liberates 
six atoms of iodine. The liberated iodine is titrated with sodium 
thiosulphate, the final reading being six times the amount of iodine 
originally present. 
The removal of chlorine by boiling is a time-consuming and 
uncertain operation. The writer has modified the above method 
by removing the excess of chlorine from solution with phenol. 
The free chlorine adds directly to the benzol ring forming an 
unionized compound which does not interfere with subsequent 
operations. This modification makes the above method accurate 
and rapid. 
