294 Chittenden and Blake—Influence of 
Our experiments were made on a setter dog, weighing 12°6 kilos. 
The animal was confined in a suitable cage, so that the excretions 
could be collected daily without loss. The food consisted of fresh 
beef and crackers, together with a suitable amount of water. The 
beef was prepared as follows: About 40 Ibs. of fresh beef, freed from 
fat, tendons, ete., was finely divided by passing through a sausage 
machine and then dried at a low temperature until it had lost about 
75 per cent. of water, and was in acondition suitable for preservation. 
50 grams of this preserved meat, together with 75 grams of the sam- 
pled crackers, soaked in 300 ¢c.c. of water, were fed to the dog twice 
daily. The meat, as determined by Kjeldahl’s method, contained 
12-4 per cent. of nitrogen, while the crackers contained 1°9 per cent. 
Hence the dog was fed daily 15°25 grams of nitrogen. 
On May 11th, the dog was put upon this diet and from the 17th on, 
the 24 hours’ urine was collected daily and analyzed. After a period 
of two weeks, during which daily analysis of the urine had shown a 
fairly constant composition, antimonious oxide was added to the diet 
in the quantities indicated in the table of results; the diet of course 
continuing the same throughout the length of the experiment. 
We deemed it better, as well as more accurate, to measure the in- 
fluence of the antimony by a daily determination of the total nitro- 
gen, sulphur and phosphorus of the urine, rather than to attempt a 
determination of urea, uric acid, phosphoric acid, etc. Nitrogen, we 
determined, according to the method of Kjeldahl,* modified slightly 
as suggested by Dr. E. H. Jenkins, of the Agricultural Experiment 
Station, viz: 5 c.c. of the acid urine were placed in a long pear-shaped 
bulb and evaporated to dryness quickly on a water bath. The resi- 
due was heated directly over a small flame with 10 c.c. of pure con- 
centrated sulphuric acid and 0:7 gram of oxide of mercury, until oxi- 
dation was almost complete. Then, a little finely powdered potassium 
permanganate was added, to render the oxidation quite complete. 
The solution was then diluted, an equivalent amount of potassium 
sulphide added to convert the mercury into sulphide, and lastly a 
standard solution of sodium hydroxide, after which the ammonia was 
driven off by boiling and collected in standard acid. 
Total phosphorus and sulphur were determined as follows : 50 c.c. 
of urine were evaporated in a capacious silver dish with 10 grams of 
potassium hydroxide and-10 grams of potassium nitrate and the resi- 
* Neue Methode zur Bestimmung des Stickstoffs in organischen Koérpern. Zeitschrift 
fiir analytische chemie, xxii, 366. 
