l86 REPORTS OF INVESTIGATIONS AND PROJECTS. 



and conducted several experiments with Eskimo men and women, in which 

 they studied the total metabolism as indicated by the excretion of carbonic 

 acid. In connection with these experiments, they provided constant weighed 

 amounts of food for the subjects, and samples of the food materials were 

 reserved for subsequent shipment. During the entire progress of the experi- 

 ments the feces and urine were also saved, and these were likewise prepared 

 and shipped, together with the foods, to the Nutrition Laboratory. In all, 

 some 200 samples of urine, 50 of feces, and 50 of foods were received. Dur- 

 ing the past year Mr. H. L. Higgins, Miss Hope Sherman, and Miss Angelia 

 Courtney have been engaged in the analysis of these materials. The Eskimos, 

 subsisting as they do on a heavy meat diet, gave admirable opportunity for 

 studying metabolism as influenced by an excessive amount of meat. The 

 results, together with the results of Dr. Krogh's experiments, will be recorded 

 in a publication in the near future. 



THE HEATS OF COMBUSTION OE SAMPLES OE BENGALIS FOOD MATERIALS. 



A most interesting memoir* has recently appeared on the diet of the Ben- 

 galis by Captain McCay, of the Calcutta Medical College. As a result of a 

 lengthy correspondence with Captain McCay, a series of samples of common 

 food materials as used by the Bengalis has been sent to the Laboratory and 

 the heats of combustion of these materials have been determined. So far as 

 we are aware, these are the first accurate determinations of the heats of 

 combustion of these food products that have been made. They throw a defi- 

 nite light upon the energy consumption of the Bengalis. 



DETERMINATION OF CARBON IN URINE. 



The compounds in normal urine are relatively few, but very complex in 

 their chemical structure. Under ordinary conditions every gram of nitrogen 

 found in the urine is accompanied by not far from 0.8 gram of carbon. In 

 determining the energy balance it is necessary to know not only the energy 

 of the food ingested, the energy of the feces, and the heat given off from the 

 body, but the energy of the unoxidized material of the urine is likewise of 

 great importance. Unfortunately it is not possible to calculate with sufficient 

 accuracy the energy present in the urine from the determination of the nitro- 

 gen, for the number of calories per gram of nitrogen may vary from 8 calo- 

 ries, the ordinary value, up to as high as 19; unquestionably in diabetes, 

 where there is a large amount of sugar in the urine, this value must be still 

 higher. It has been found, however, that the energy per gram of carbon in 

 the urine is remarkably constant. If it is possible, therefore, to determine the 



*D. McCay : Standards of the constituents of the urine and blood and the bearing of 

 the metabolism of Bengalis on the problems of nutrition. Scientific Memoirs, n. s., 

 No. 34, Calcutta, India. (1908.) 



