244 VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



ever, the variations are plus or minus, leaving no difference between 

 the average areas for the whole squad when measured by either method, 

 while on January 5 there was a tendency, as with Squad A at the 

 beginning of the experiment, for the linear formula to give slightly 

 higher values than with the height-weight chart. 



Comparing the areas for Squad A, as obtained by the photographic 

 method, with those computed from the Du Bois measurements, we 

 find that there are minor variations, but that on the whole the averages 

 of the three measurements show that the total areas as determined 

 by the three methods are essentially alike. The averages for Squad 

 A for September 29 are 1.84, 1.79, and 1.83 sq. meters, for the Du Bois 

 formula, height-weight chart, and photographic method, respectively. 

 On November 24, the averages are 1.73, 1.71, and 1.72, respectively. 

 On February 2 the areas computed from the photographs are in most 

 instances smaller than they are by the linear formula, the widest dif- 

 ference being with Gul, 1.72 against 1.63 sq. meters, or 0.09 sq. meter. 

 The average areas for the three methods are 1.73, 1.72 ,and 1.68 sq. 

 meters, respectively. 



With Squad B the area computed from the photographic method 

 on January 5 is, in almost every instance, somewhat lower than that 

 obtained by the linear formula, the widest difference being with Sch, 

 1.84 sq. meters as against 1.75 sq. meters. The averages are 1.84, 

 1.81, and 1.79 sq. meters. On January 27 a comparison of the two 

 methods likewise shows somewhat lower values with the photographic 

 method than with the Du Bois method. The averages for the three 

 methods are 1.77, 1.77, and 1.72 sq. meters. 



In addition to the 23 subjects given in tables 18 and 19, a single series 

 of measurements was made with three other subjects, and the body sur- 



Table 20. — Body-surface measurements, supplementary data. 



face obtained by the three methods. These were Fre, on September 

 29, 1917, McM on January 5, and Lon on January 27, 1918. The 

 values for these three subjects are given in table 20 as supplementary 

 evidence. These values show essentially the same picture as those 

 for the larger group of 23 men. 



We may, perhaps, make the best comparison of the two methods by 

 computing the factor to be used in the photographic method for each 



