NUTRITION LABORATORY. 301 



difference in skin-temperature at different parts of the body make a 

 study of the radiation from the body desirable. Thanks to the coopera- 

 tion of Dr. C. G. Abbot, a large number of observations of the direct 

 radiations from the nude human body at different temperatures and 

 at different parts of the body were made in the spring of 1921. 



Influence of food upon metaholism. — The selection of a light though 

 satisfying meal, that can be given hospital patients and even normal 

 subjects, which would eliminate the 12-hour fasting period commonly 

 required for metabolism measurements, is greatly to be desired. 

 Taking advantage of the quite unusual degree of repose of the artist's 

 model used in many of our other respiration experiments and studies, 

 we have been making studies upon light diets, and noting their influ- 

 ence upon metabolism. These studies were made with the cooperation 

 of Miss Marion L. Baker. 



Conversion of carbohydrate to fat in the animal body. — This particular 

 phase of nutrition has been studied for several years, and the extra- 

 ordinarily high respiratory quotients observed have been tested by 

 two entirely independent methods. The calorimeter for direct mea- 

 surements of heat under these conditions has been further improved, 

 and, as has been previously stated, the general principle is shortly to 

 be applied to human calorimetry. Miss Alice Johnson assisted in 

 this study. 



Metabolism during mental effort. — A renewed interest in the effects of 

 mental work upon physical condition, which have been so universally 

 noted, has led to the institution of a research upon the relation between 

 mental effort and metabolism. New technique, with graphic regis- 

 tration of respiratory depth and rhythm, promises most interesting 

 results. 



Metabolism of farm animals during growth. — In cooperation with 

 Professor E. G. Ritzman, of the New Hampshire Agricultural Experi- 

 ment Station, Durham, New Hampshire, and using the large respira- 

 tion chamber installed in Durham by the Nutrition Laboratory, an 

 extensive series of investigations has been under way during the entire 

 year, in which observations have been made of the growth changes of 

 calves and particularly of sheep. Several groups of ewes before and 

 during pregnancy have also been studied. The work is still in prog- 

 ress. Professor Ritzman is assisted by Miss Helen L. Hilton. 



Metabolism of birds. — This research, which has been conducted at 

 the New York Zoological Park, through the cordial cooperative spirit 

 of Director W. T. Hornaday and Mr. L. S. Crandall, the curator of 

 birds, has been completed and the apparatus returned to the Nutrition 

 Laboratory. The observations were in the hands of Mr. E. L. Fox. 



Metabolism of snakes. — A review of the earlier observations made at 

 the New York Zoological Park on the metabolism of snakes, particu- 

 larly during the digestive cycles and with differences in environmental 



