LATER INVESTIGATIONS 17 
Among the methods used for measuring the amount of muscular work 
performed in connection with respiration experiments, mention should be 
made of a form of ergostat devised by Jaquet and described by H. Christ. 01 
As the subject stepped upon this machine, the height of each step could be 
measured, and the total height multiplied by the body-weight gave the total 
amount of muscular work performed. The studies made by Jaquet and Sven- 
son 6 with this ergostat consisted of experiments with fat individuals in which 
the Zuntz-Geppert respiration apparatus was used to measure the gaseous 
metabolism. Jaquet also studied the after-effects upon the respiratory ex- 
change of muscular work incidental to mountain-climbing, using a Zuntz- 
Geppert apparatus. He later repeated these experiments with a Speck 
apparatus and a spirometer containing 100 liters." 
Finally, in any resume of the work done by Zuntz and his associates, 
mention should be made of the interesting experiments of Kolmer on swim- 
ming. 6 * During these experiments he found that the oxygen consumption was 
increased over that during resting 9 times, nearly 20 per cent greater than the 
amount required for rapid mountain-climbing, thus showing the enormous 
metabolism during the operation of swimming. 
The active interest of Zuntz and his associates in the metabolism during 
marching and mountain-climbing has resulted in a large number of contribu- 
tions on this subject from Zuntz' laboratory and from Durig. e The difficulties 
incidental to computing the amount of external muscular work performed in 
climbing mountains are obvious, but the observations with the treadmill 
are of direct mathematical value. The results of the investigations made by 
Zuntz and other workers who used the Zuntz-Geppert apparatus have been 
admirably brought together in a number of publications/ 
INVESTIGATIONS IN THE FRENCH LABORATORIES. 
Investigations in the French laboratories on the question of muscular 
activity and metabolism have been carried out extensively by Chauveau, 
Tissot, Laulanie, and, more recently, by Amar. Chauveau ■ in 1899 repeated 
the experiments of Hirn, using a treadwheel and determining directly the 
heat radiated from the body. The emission calorimeter was used, and no 
correction was made for the heat of water vaporized. The air was collected 
in a Tissot spirometer, the samples being taken in 3 periods of 2 minutes each h 
at the beginning, middle, and end of the experiment. Since the calorimetric 
measurements were made during the last part of the experiment, only those 
results obtained from the analyses of the samples collected in the last period 
should be used for comparison with the calorimetric measurements. Although 
dealing exclusively with the respiratory quotient, i. e. f the character of the 
« Christ, Deutsch. Archiv f. klin. Med., 1894, 53, p. 102. 
ft Jaquet and Svenson, Zeitschr. f. klin. Med., 1900, 41. p. 17. 
c Jaquet, Archiv f. exp. Path. u. Pharm., 1910, 62, p. 341. 
d Zuntz, Loewy, Muller, and Caspari, Hohenklima u. Bergwanderungen, Berlin, 1906, p. 263. 
• Zuntz, Loewy, Muller, and Caspari, Ibid. Durig, Physiol. Ergebnisse der im Jahre 1906 Durchgefuhrten 
Monte Rosa Expedition. Besonders Abgedruckt aus dem LXXXVI Bd. Denkschriften der Mathe- 
matisch-Naturwissenschaftlichen Klasse der Kaiserlichen Akademie der Wissenschaften, Wien. 
/ Zuntz, Loewy, Magnus-Levy, and others in Oppenheimer's Handbuch der Biochemie. Zuntz and Schumberg, 
Physiologie des Marsches, Berlin, 1901. Magnus-Levy, Physiologie des Stoffwechsels, in von Noor- 
den's Handbuch der Pathologie des Stoffwechsels, Berlin, 1906, 1, p. 379. 
9 Chauveau, Comptes rendus, 1899, 189, p. 249. 
1* For a criticism of the length of the experiments see Weiss, Physiologie generate du travail musculaire et de 
la chaleur animate, Paris, 1909, p. 142. 
