MEASUREMENTS 



299 



account. If h is the ordinate of a curve due to the flexion of the 

 forearm relatively to the arm, the corresponding work done will 

 be: 



r Phr 2 



T = P X h 



r 

 X 



Rr' 



224. The modifications of Mosso's apparatus necessary to make 

 an ergograph of the legs will now be considered. These were due 

 to Capobianco (*) (fig. 212). The fixed portion is a boot made of 

 fine and strong cloth with a rigid sole of wood or iron. This is 

 fixed on a support of convenient size, having a spur to which is 

 attached catgut passing over a pulley r on a level with the support. 



The cord is attached to the usual Mosso slide, with its style S 

 and weight P. The subject sits on a chair, the thigh being held 

 by a strap, and the leg being a little bent. He raises the heel 

 whilst the point of the foot remains fixed to a hinge. Under a 

 weight of 20 kilogrammes, the contraction of the crural triceps 

 causes rapid fatigue, and the ergograms obtained are very similar 

 to those for the middle finger. 



The technique of ergography need great attention to avoid 

 muscular associations and pain.( 2 ) 



F.G. 212. 



Capobianco's ergograph for the leg. 



225. The Measurement of Industrial Work. The principal 

 object of ergographs is to investigate the decrease of work under 

 the influence of fatigue. 



Marey's graphic method only allows the measurement of the 

 muscles applied in the handling of a given tool. The arrange- 

 ments described herein for the measurement of muscular effort 

 are also applicable for the measurement of work. 



( x ) F. Capobianco (Arch. Ital. BioL, vol. xxxvii., p. 123, and especially 

 Monitore Zoologico Ital. No. 7, 1901). 



( 2 ) Consult Holmes (Journ. ofAmer. Med. Assoc., Dec. 1903), and Hellsten 

 (Skand. Arch.f. Physiol., vol. xvi., 139, 1904); A. Imbert (Comptes Rend. Ac. 

 Sc., 31st, Oct. 1910). 



