THE RELATIVE CONTRIBUTION OF THE STAPLE 



COMMODITIES TO THE NATIONAL FOOD 



CONSUMPTION.^ 



By RAYMOND PEARL. 



(Read April 24, 1919.) 



The purpose of this paper is to present a part of the more im- 

 portant results of a detailed and comprehensive investigation of the 

 food resources and utilization of the United States. The complete 

 study will appear presently in another form, and then the supporting 

 data on which the results here presented are based will be available. 

 Only the final results as to consumption of Jiuinan food will be 

 given in the present communication. 



It is quite impossible to present here any account of the critical 

 precautions used to ensure accuracy, nor can the details of how the 

 final results on consumption were arrived at be given in this brief 

 paper. It is hoped that the indulgence of the reader will be granted 

 until the appearance of the complete publication,- where all the 

 details are set forth. 



I. The Plan. 



The basis of any adequate survey of food resources must be 

 essentially physiological, rather than one of commodities or trade. 

 Broadly speaking the ultimate sources of food are the soil and the 

 sun. The energy derived from the sun through the mechanism of 

 the green plant builds up the inorganic chemical elements of the soil, 

 air, and water into compounds which can be utilized as food by man, 

 either directly or secondarily in the form of the products of animals 

 which have been nourished on the primary foods of the plant world. 



For the purpose of statistical analysis all nutritive materials pro- 



1 Papers from the Department of Biometry and Vital Statistics, School 

 of Hygiene and Public Health, Johns Hopkins University. No. 4. 



~ Pearl, R., " The Nation's Food." In process of publication by the W. 

 B. Saunders Co., Philadelphia. 



182 



