OFFICE OF EXPERIMENT STATIONS. 287 



foods in the ordinary American diet. Meat and vegetables were used 

 in addition to rice. In the ease of tlie professional man's family and 

 the laundry association the effect of environment was more marked 

 than in the case of the truck-farm laborers — that is, the diet of per- 

 sons residing in or near a large town was more influenced by Ameri- 

 can conditions and more American foods were eaten than was the 

 case with the men living in the country. 



Experiments on the Metabolism of Matter and Energy in the Human 

 Body, 1898-1900, by W. O. Atwater and F. G. Benedict (Bulletin No. 109, 

 pp. 147): Continuing earlier work, experiments are reported which 

 test the accuracy of the respiration calorimeter and metabolism exper- 

 iments with man in which the balance of income and outgo of nitro- 

 gen, carbon, and energy was determined, the special object being to 

 compare the nutritive value of fats and carbohydrates. Nine such 

 metabolism experiments were made. The work is reported and dis- 

 cussed in detail, the bulletin concluding with summaries on the fol- 

 lowing topics: Food materials supplied and consumed and the differ- 

 ences in demand by men at rest and at work; the total elimination of 

 water during day and night under different conditions of work, as 

 well as the i)roportion of the total amount eliminated in the respira- 

 tory products and as persi^iration; elimination of carbon dioxide dur- 

 ing day and night and during different conditions of work and rest; 

 the elimination of energy as heat and external muscular work; the 

 amount of energj^ liberated by the body at different periods of the 

 day; the relation between the elimination of heat and carbon dioxide 

 in the body. In connection with this discussion a number of average 

 values are given, such as those for the diurnal variation in the amount 

 of water eliminated in the respiratory jDroducts. Similar values based 

 on less experimental data have long been quoted in tables of physio- 

 logical constants and general text-books. The present bulletin, it is 

 believed, supplies values which are much more reliable than those 

 which have been generallj^ quoted in the past. 



Principles of Nutrition and Nutritive Value of Food, by "VV. O. 

 Atwater (Farmers' Bulletin No. 142, pp. 48) : This bulletin includes 

 a discussion of the general principles of nutrition, dietaries and diet- 

 ary standards, digestion experiments, the comparative nutritive and 

 economic value of different foods, effects of cooking and related top- 

 ics, the whole being designed as a summary of results obtained up to 

 the present time in the nutrition investigations conducted under the 

 auspices of this Office. 



Dietaries in Public Institutions, by W. O. Atwater (Yearbook, 

 Department of Agriculture, 1901, pp. 393-408) : The general problem 

 of feeding large numbers of persons under uniform conditions is 

 discussed and work which has been carried on along such lines 

 summarized with especial reference to the author's investigations 

 conducted in New York State asylums for the insane under the aus- 

 pices of the State commission in lunacy. It was found that in many 

 cases it was possible to materially improve the diet and at the same 

 time lessen its cost. 



Scope and Results of the Nutrition Investigations of the Office of 

 Experiment Stations (Annual Report of the Office of Experiment Sta- 

 tions, 1901, i)p. 437-482): The jKirpose and scope of the nutrition 

 investigations conducted underthe auspices of this Office is outlined, 

 and the methods of conducting the investigations recorded and the 

 results obtained to date discussed. The report also contains histor- 

 ical and descriptive matter concerning all the investigations conducted 



