MEASUREMENTS 



281 



M 



FIG. 1t5. 



to the other branch by a rigid rod, 

 The man grasps the handle P (fig. 176). 



The effort is registered by a receiving 

 tambour connected with T. 



A handle of the same kind can be 

 used to measure the effort in support- 

 ing the handles of a wheelbarrow. 

 Prof. Imbert fixes the spring to two 

 metal pieces, M and M', the one 

 soldered to the handle P 



In these conditions, " when the 

 workmen, holding the handle of the 

 truck by the sleeve, M, exerts a 

 pushing or pulling effort, this effort 

 causes the sleeve M to slide to a 

 degree limited by the spring R, the 

 movement being transmitted to the 

 membrane of the tympan f 1 ) (fig. 

 175). Thus the efforts that are 

 perpendicular and parallel to the 

 handles will be inscribed on a 

 cylinder by receiving tympans con- 

 nected to the transmitting tympans. 



211 . In the handling of the cabrouet 

 as in the displacements of loads- in 

 general, the load should be carried 

 on a vehicle by pulling it. Imbert 

 uses for this purpose an oval spring 

 with a handle, P, and a Marey's 

 tympan on one of its branches, joined 



FIG 170 



FIG. 177. 



(fig. 177) 



and the 



other to 



a ring, A, fixed to the handle of 



the wheelbarrow. 



Thus the effort of support will 

 deform the spring, and the defor- 

 mations will be transmitted to an 

 indiarubber bulb, C, placed in a 

 metal cup, through the medium of 

 a small disc, the bulb being con- 

 nected to a receiving tambour. 



The learned professor, of Mont- 

 pellier, improved the method of 

 measuring the effort parallel to the 



A. Imbert (loc. cit., p.p. 3-5 ; separate reprint, 1906). 



