18 MUSCULAR WORK 
katabolism, the experiments on Tissot reported by Chauveau a should be 
cited. The work was done by going up and down stairs, and the gaseous 
exchange studied by the Chauveau-Tissot apparatus. 
Laulanie's experiments b were made chiefly with animals, but Amar in 
1910 c studied the effect of bicycling upon the metabolism of men. Using a 
bicycle ergometer, the Chauveau-Tissot valves, and a dry gas-meter, he made 
experiments on the natives in Algeria, collecting and analyzing samples of 
the expired air. In his observations special emphasis was laid upon a study 
of the mechanical efficiency of the body as a machine. These values will be 
referred to subsequently. Amar's monograph contains an excellent resume 
of the earlier literature with particular emphasis upon the work carried 
out in the French laboratories. The percentage of efficiency is given special 
treatment.** 
A later research of Amar e deals with the muscular work involved in 
filing a piece of metal. With a most ingenious arrangement of tambours 
and dynamometer springs Amar made a series of experiments both with an 
apprentice and a skilled machinist. A study of the gaseous exchange was 
made in many of the experiments. As was to be expected with this form of 
work low efficiencies were found. 
INVESTIGATIONS BY THE CHAMBER METHOD. 
The principal investigations on muscular work by the chamber method 
were made by Sonden and Tigerstedt in Stockholm, Rubner in Berlin, and 
Atwater and his associates in Middletown, Connecticut. 
Employing the large Sonden-Tigerstedt respiration chamber in the 
Karolinska Institute in Stockholm, Sonden and Tigerstedt f carried out a 
series of investigations studying only the effect of muscular work upon the 
carbon-dioxide output, their apparatus not being designed for determining 
the oxygen consumption. Several forms of muscular activity were used, the 
study including experiments in which the subject walked about the chamber, 
the distance traveled being measured by means of a pedometer, and experi- 
ments in which the subject climbed up and down a ladder placed inside the 
chamber. The Gaertner ergostat and the Fick dynamometer were also 
employed. In reporting these researches, Sonden and Tigerstedt computed 
the results obtained by earlier workers with reference to the relationship 
between the carbon-dioxide production and muscular activity so as to make 
them comparable with their own results. This comparison is given in table 3, 
which is taken from the report of Sonden and Tigerstedt." 
Using a special form of ergostat, in which the arms and muscles of the 
back were employed, Johansson h made a series of experiments in which he 
raised a weight to a given distance, the amount of work ranging from 600 to 
7,000 kilogrammeters. Placing the apparatus inside the Sonden-Tigerstedt 
respiration chamber, he determined the carbon-dioxide production for each 
kilogrammeter of external muscular work, concluding from his results that 
a Chauveau^Comptes rendus, 1896, 122, p. 1163. 
° LaulaniS, Elements de physiologie, 2d ed., Paris, 1905. 
* Amar, Le rendement de la machine humaine. Reeherches sur le travail, Paris, 1910. 
t See also Weiss, loc. cit. 
« Amar, Journal de Physiologie et de Pathologie generale, 1913, 15, pp. 69 and 102. 
/ Sonden and Tigerstedt, Skand. Archiv, 1895, 6, p. 1. 
Sonden and Tigerstedt, loc. cit., p. 202. 
ft Johansson, Skand. Archiv, 1901, 11, p. 273. 
