DEELEY TORSION MACHINE. 203 



portion, under a maximum twisting moment of 120,000 

 inch-pounds. 



On Fig. 35, p. 8(5, will be seen the large worm wheel 

 used for the torsion tests on Professor Elliot's machine, 

 on the side of the lever remote from the observer. 



113. Messrs. Greenwood and Batley's Torsion 

 Gear. The machine illustrated on Fig. 30. p. 78, is 

 in some cases provided (in addition to the appliances 

 for testing in tension, compression, and bending) 

 with additional gear to be used for carrying out 

 torsional tests. On referring to this illustration, it will be 

 noticed that there are two holes through the main bed of 

 the machine. These form bearings wherein turn a pair of 

 flanged wheels, these wheels carrying sockets in their 

 centres for holding the two outer ends of a torsion 

 specimen. Each of these wheels is provided with a chain 

 attached to its rim and passing from the wheel horizontally 

 and linked to the movable crosshead of the machine. By 

 means of this piece of apparatus the outer ends of the 

 apparatus are rotated together and the strain taken up. 

 The middle portion of the specimen between the wheels 

 is taken hold of by the lower end of a short vertical lever, 

 the upper end of which is connected through a horizontal 

 link with the system of weighing levers. The pull on the 

 end of the twisting lever, and, therefore, the moment on 

 the specimen, is measured in this way, the strain being 

 taken up by moving the sliding crosshead outwards along 

 the bed of the machine. The specimens tested in this 

 machine are of necessity short, 



The holes through the centres of the chain wheels are 

 square in shape to receive the ends of the specimens, and 

 they are also fitted with square dies having smaller square 

 holes to receive specimens of smaller size. 



114. Deeley Torsion Machine.* This machine, invented 

 by Mr. R. M. Deele}', is in use at the Midland Locomo- 

 tive Works, at Derby, and possesses some novel features 

 which are worth noticing. Three views of the machine 

 are shown in the accompanying illustrations (Figs. 96, 97, 

 and 98), an end elevation, a section, and a side elevation. 

 In this machine, as before, one end of the specimen is held 

 in the boss of a worm-wheel C, while the other is secured 



* Proceedings Institution of Mechanical Engineers, October, 1898. 

 Mr. Feet's paper. 



