BELT POWER TRANSMISSION. ; LXXXV. 
At the end of the lever the two cylinders of H and J, witha 
common axial centre, received the direct connected plungers (H 
and J), one, the larger, acting upward into the cylinder with air 
chamber attached, and the other downward into a cylinder con- 
nected as before stated to the tension cylinder (G). The end of 
the lever passed through an eye in the plungers (H and J). The 
rotation was to lift the lever ; in so doing the pressure was released 
(G) and the brake slackened. 
The load was applied by admitting water under pressure to the 
top cylinder (H) the pressure was partly transmitted to (J) thence 
to the tension cylinder (G) by oil in the connections. Any 
tendency of the lever to fall by more than the load applied was 
counteracted by the tightening of the brake, conversely any 
tendency of the lever to rise by more than the load applied at its 
end was to release the pressure in the tension cylinder and to 
slacken the brake. Thus the brake was automatic in action. All 
that the observer had to do was to admit water slowly into the 
air cylinder (H) till the tension on the brake caused the belt to slip, 
The load in pounds on the end of the lever was read off a specially 
graduated pressure gauge calibrated to the exact area of the larger 
plunger (H), and from this reading was deducted the pressure 
transmitted to the lower plunger (J) as shewn by a similarly 
Specially calibrated gauge. 
The friction on the plungers (H, J) was almost entirely obviated 
by giving the plungers a semi-rotary movement during the appli- 
cation of the load. The error due to this source apparently did 
not exceed one per cent. 
The machine was driven by a portable twin-cylinder engine, 
developing by reference to an electric output nearly fifty (50) 
horse-power. During the tests the engine was driving a dynamo 
on reduced output, which served admirably to steady the engine. 
The engine-driver, standing by the throttle valve during the 
| experiment, was guided by the reading of a voltmeter and was 
____ able to keep the speed fairly constant. The speeds on the dynamo- 
