148 Modifications of a Form of Spherical Integrator. 



fixed upon a frame, while two others K L, held in a frame 

 SMNV (fig. 2) rocking about points at S Y, keep the sphere 



Fig. 2. 



in compression ; the frame is so moved, by means of a slot R 

 attached to the spring rod of the dynamometer, that the line 

 P M, and therefore the circle on the sphere rolling upon the 

 cylinder D, is proportional to the tension of the driving-belt ; 

 the cylinder K is driven at a rate proportional to the velocity 

 of the belt-speed, and the cylinder I) is attached to a revo- 

 lution-counter. When the tension of the belt is constant, then 

 the revolution of D is proportional to the velocity. When 

 the velocity is constant, the revolution is proportional to the 

 tension of the belt. When both velocity and tension vary 

 together, then the revolution of D is proportional to the pro- 

 duct of velocity and tension which is the work at any instant, 

 and the number of revolutions of D during any time is pro- 

 portional to the work done during that time, and shows, 

 therefore, how much energy has been transmitted by the 

 dynamometer. 



In the figures, for the sake of clearness, the frame which 

 carries the cylinders is omitted. The instrument which the 

 author of this communication has arrived at, is quite unaffected 

 by any rapid change either of velocity or tension of belt that 

 may take place while it is running. The beautiful three-wheel 

 spherical integrator of Prof. Hele Shaw, which was applied 

 to the dynamometer, as long as it had to deal with slowly 

 varying velocity, acted very well indeed ; the idea of changing 

 the direction of the angle at which the poles of the sphere lie 

 in is taken from it. 



Algiers, March 1886. 



