100 Proceedings of Royal Society of Edinburgh. [sess. 
This modification has been tested with Merck’s allantoin, which 
itself was found to be pure by determining the nitrogen by 
Kjeldahl’s method. 
When dried in a desiccator, '5 grm. was found to yield *49 grm. 
The loss during each stage of filtration was calculated, and left 
.46 grm. to be recovered, as the final filtrate was estimated as an 
aliquot portion. The actual recovery was *46 grm. or 100 per 
cent. In another experiment 99*6 per cent, was recovered. 
( B ) Other Estimations. 
The total nitrogen was estimated by Kjeldahl’s method. 
Methods of Experiment. 
For the experiments the animals used were a setter and retriever 
bitch — each of known weight — and the urine was collected into 
dilute hydrochloric acid. 
B. Results. 
The allantoin excretion was first found on a diet of oatmeal and 
milk, the quantities being 300 grm. oatmeal and 700 c.c. milk. 
Oatmeal contains *0212 per cent, purin nitrogen, and milk *002 grm. 
per litre, according to Dr Walker Hall. From this one finds that 
the diet of oatmeal porridge and milk contains *065 grm. purin 
nitrogen. 
Table I. 
Allantoin per diem upon oatmeal and milk diet. 
1-140 grm. 
0*901 „ 
0*7)12 „ 
0*683 „ 
Average, 0*809 ,, = 0*28 hh 
The animals were then fed upon weighed quantities of thymus 
gland or other substance to be studied. The thymus gland of the 
ox was procured from the butcher, and the fat determined in a 
sample. Having estimated the amount of fat, the animal to be 
experimented upon was fed upon a known weight of thymus 
gland, deduction being made for the amount of fat. 
