88 BAILEY TESTING MACHINE. . . 



and put the keys in afresh. A third crosshead K, which 

 is also capable of sliding along the frame into any 

 desired position, is used for compression tests, and as 

 the middle crosshead can also be moved by the 

 screws, great facilities exist for easy and rapid changes 

 being made. The second advantage possessed by the 

 machine is that the second lever is a long one of the usual 

 Buckton-Wicksteed double-ended design, and provided 

 Avith a poise weight of invariable magnitude, so that the 

 trouble of changing the loads is avoided and all tests are 

 carried out with the same load. It may also be pointed 

 out that the distance between the weighing levers and the 

 cylinders is shorter than usual, and, therefore, there is less 

 recoil at the point of rupture. 



In the 100-ton Cardiff machine the jockey weight is 

 10 cwt. or half a ton. 



Fig. 30 shows a view of the left-hand end of this 

 machine when being used for a bending test. 



43. Lesser flachines. Most of the machines which 

 have been so far described are capable of exerting loads 

 varying from 50 to 450 tons. Such are necessary for 

 testing of specimens of any considerable size, but there are 

 also a great many machines in use for testing specimens of 

 much smaller dimensions and under much smaller loads. 

 One machine of this smaller kind has already been described, 

 namely, the 5-ton machine of Messrs. Buckton. Many 

 other makers turn out smaller machines of various sizes. 



Messrs. Greenwood and Batley have built a variety of 

 machines in addition to those already mentioned, varying 

 in capacity from 50,000 Ib. to 2,400 Ib. The largest of these 

 are of the double-lever horizontal type ; many of the 

 smaller ones are of the single- 1 . ever vertical type, not 

 unlike the Buckton-Wicksteed design. 



Another firm who make small single-lever machines 

 suitable for testing bars up to about in. diameter are 

 Messrs. S. Denison and Sons, of Leeds. 



44. Technical School Pattern of Sir W. H. Bailey. 

 On Fig. 37 is illustrated a small testing machine designed by 

 Sir W. H. Bailey, of Salford, for use in the laboratories of tech- 

 nical schools and for the purpose of illustrating lectures. 

 The machine consists of a cast-iron bed supported upon two 

 standards ; of a lever load-measuring apparatus at the left- 

 hand end of the bed ; and an hydraulic straining cylinder 

 towards the right-hand end. A tension test piece is shown 

 in position. Its right-hand end is held in wedge grips in 



