DU BOIS: BASAL ENERGY REQUIREMENT OF MAN 351 



made experiments on many individuals under a great variety of 

 conditions. Their bed calorimeter in particular has been of 

 great service in the study of the basal metabolism. 



The most ingenious apparatus constructed for the study of 

 metabolism is the small calorimeter of Langworthy and Milner. 

 In this the temperature control is automatic and small electrical 

 instruments day after day perform work that exhausts an expe- 

 rienced man after a few hours. Most calorimeters require two or 

 three men in constant attendance, but theirs will run accurately 

 all by itself. 



The small calorimeter constructed by Dr. H. B. Williams for 

 Lusk at the Cornell University Medical College in New York 

 City has given results which are technically perfect even in 

 short experimental periods. Only those who have worked in the 

 subject can appreciate the brilliant planning of Lusk's experi- 

 ments on dogs and their profound significance in the study of 

 the fundamental laws of metabolism. As a result of this work 

 on animals and some work on patients with the small "unit" 

 respiration apparatus devised by Benedict, it seemed advisable 

 to construct a calorimeter for the study of disease. This was 

 made possible by the trustees of the Russell Sage Institute of 

 Pathology, who supplied funds to Dr. Lusk sufficient for the 

 construction and maintainence of a calorimeter and metabolism 

 ward in Bellevue Hospital, New York. 8 



This apparatus, which was built by Riche and Soderstrom, is 

 the latest development of the apparatus of Atwater and Rosa 

 as improved by Benedict, Milner, Williams, and others. It is 

 about the size of the lower berth of a sleeping car and is provided 

 with a comfortable bed, a shelf and a couple of windows. The 

 subject of the experiment lies quietly for three or four hours in 

 the well ventilated box at a comfortable temperature. During 

 this time his heat production is being measured by the inde- 

 pendent methods of direct and indirect calorimetry. 



The direct method depends on the physical measurement of 

 the heat of radiation and conduction and also of vaporization, 

 about one quarter of the total heat produced being eliminated 

 by evaporation of water from skin and lungs. The indirect 



2 Archives of Internal Medicine, 15: 793. 1915. 



