242 



VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



Table 19. — Body-surface measured by different methods — Squad B. 



the Du Bois measurements, also the factors used in the linear formula 

 are shown in the typical series of measurements given in table 16. The 

 method of computing the body-surfaces from the profile photographs 

 is as follows : 



From an extensive series of photographs and measurements of men 

 and women it was found that when the planimetered area of a 

 photograph giving a profile view of a subject with left arm extended^ 

 was referred to a photographed meter scale, its relation to the total 

 area of the body was represented by the average factor 5.02. In 

 other words, the area of the planimetered section referred to the 

 meter scale, when multiplied by 5.02, gave the total area of the 

 body as computed by the Du Bois formula. Usually in planimeter- 

 ing, the photograph is divided into two approximately equal parts 

 by an arbitrarily drawn line passing through the hips. The upper 

 and lower sections are then planimetered separately and the sum of 

 the two areas, which on our instrument is expressed in square inches, 

 is multiplied by the factor 6.45 for conversion to square centimeters. 

 The length of the meter scale in the photograph is then found in milli- 

 meters and the true area of the surface shown in the photograph ob- 

 tained by a simple proportion. Thus, using the photograph of 

 Greyson C. Gardner {Gar, fig. 78) as an illustration, we found that the 

 lower part of the body gave an area by planimetering of 1.78 square 

 inches and for the upper part of 2.31 square inches, the total area of the 

 photograph being 4.09 square inches. This, reduced to square centi- 

 meters by means of the factor 6.45, gave a total area for the photo- 

 graph of 26.4 sq. cm., or 0.00264 sq. meter. The meter scale in the 

 photograph measured 87.5 mm. or 0.0875 m. The proportion used for 

 calculating the actual surface of the body shown in the photographs 



^ Our so-called "pose C." See Benedict, Am. Journ. Physiol., 1916, 41, p. 275. 



