562 EXPERIMENT STATION EECOED. 



The authors couclnde that work may be called light or moderate when the 

 respiratory excretion of carbon is not greater than -16 gm. per hour. This 

 would be the case with the work of tailors, bookbinders, and shoemakers. 

 When the respiratory carbon excretion is from 16 to 30 gm. per hour the work 

 is designated as severe. To this group would belong metal workers, painters, 

 or carpenters. When the respiratory carbon excretion exceeds 30 gm. per 

 hour the work is called very sevei'e. To this group would belong stone masons 

 and wood sawyers. In the case of the women sewing either by hand (7.5 to 

 8 gm. carbon per hour) or by machine (9.35 to 10.78 gm. carbon per hour) is 

 regarded as relatively light work, much the same as that of a bookbinder (8.88 

 to 11.5 gm. carbon in respiratory products per hour). The authors are of the 

 oi^inion that women's work can be called light when it does not cause a respira- 

 tory excretion of more than 20 gm. per hour. The respiratory excretion in the 

 case of the laundresses was 16.91 and 25.91 gm. per hour on an average. In 

 the case of the two subjects engaged in housework it was 13.01 and 20.7 gm. 

 per hour on an average. 



From the amounts of respiratory carbon excreted per hour and the energy 

 required by the body for maintenance, the authors compute the energy expendi- 

 tures for the work alone in the different experiments. These are found to 

 range from 44 calories per hour with the tailors to 406 calories per hour with 

 the wood sawyer, and in the case of the women from 4 calories per hour with 

 one of the women engaged in sewing by hand to 214 calories in the case of the 

 woman engaged in laundry work. The computed amount of work in an 8-hour 

 day ranged from 29,920 kgm. with the tailors to 276,080 kgm. with one of the 

 subjects sawing wood, and in the case of the women from 16,320 kgm. in the 

 case of one of the women working with a sewing machine to 106,760 kgm. witli 

 one of the women engaged in housework. The seamstresses engaged in hand- 

 work were not included in this calculation, but would differ little from those 

 who worked with the machine. 



The general deduction is that men engaged in light or moderate muscular 

 work produce up to 60,000 kgm. ; in severe work up to 160.000 kgm. ; and in very 

 severe work up to 280,000 kgm. and more. In the case of women, the expendi- 

 ture in light or moderate work is up to 40,0(X) kgm. ; in severe work up to 

 100,000 kgm. ; and in very severe work up to 145,000 kgm. and more. The total 

 energy production per day as calculated, ranging from 2,000 to 6,000 calories, 

 was very much the same as the energy supplied in the diet (2,300 to 6,300 

 calories). The authors note that the enei'gy supplied in the experimental diet 

 was somewhat smaller than it should have been in the case of shoemakers, 

 tailors, and metal workers, but they are of the opinion that rather more work was 

 done in the calorimeter chamber than would be under ordinary circumstances. In 

 the case of the carpenter and the wood sawyer the energy supplied in the ex- 

 perimental diet was very close to the enei'gy production. 



Since the energy supplied in the diet in these experiments was in accord with the 

 requirements as expressed by the usual dietary standards, they believe that these 

 are reasonable with respect to the energy which should be provided for persons 

 engaged in muscular work. 



The relation between gaseous exchange and surface area at extreme 

 temperatures, E. Gotsch {Uher die Beziehungen dcs Rcsjnratorischen Stoff- 

 wechsels zur Eorpcroherflache hci Extrcmen Ausscntenrperaturen. Inuug. 

 Diss., Univ. Leipsic, J912, pp. ^2, figs. 3; Arch. Anat. u. Physiol., Physiol. Abt., 

 No. 5-6 (1912), pp. Jt21-459, figs. 3). — A small respiration apparatus was used 

 for these experiments with laboratory animals (guinea pigs). 



According to the author's conclusion, Rubner's rule that the carbon dioxid 

 production at constant temperature is proportionate to the surface area has a 



