WEST WALLSEND-KILLTNG WORTH COLLIERY. 283 



The shafts are 620ft. deep, the downcast being 16ft. in 

 diameter, while the upcast or air shaft is 15ft. in diameter. 

 The downcast shaft is surmounted by a steel head-frame, and 

 adjoining it is a wooden heapstead (Fig. 183). The hoisting- 

 engine is one of Grant and Ritchie's, with 29in. cylinders; the 

 drum is cylindro-coiiical, having 12ft. and 14ft. diameters. 

 The cage is suspended from the rope by six chains, one in each 

 corner, and two in the middle. Those in the middle hang 

 slightly loose, so as not to take any of the weight, being only 

 required in case of emergency should the others break. Chairs 

 are pushed forward under the cage by the banksman on the 

 arrival of a cage at the surface, but the chairs are pushed back 

 again out of the way by the off-going skips striking a trigger : 

 so as soon as the on-coming skips have pushed the others off 

 the cage, and taken their places, everything is in readiness for 

 the engine-driver to lower away. 



The haulage underground, as in the case of the West 

 Wallseiid, consists of three endless rope systems worked by a 

 strap rope from the surface and thrown in and out of gear by 

 clutches as required. Ventilation is carried out with the help 

 of a 35ft. diameter Gruibal fan. 



The number on a miner's token varies with the place 

 where he is working, but the number of his lamp is always- 

 the same, and a token is hung up on a peg when his lamp i& 

 taken below. In this way the management can ascertain how 

 many and what men are at work, and where they are employed. 



The side tipplers are put in motion by a wheel, which is 

 always revolving, but which is only brought in contact with 

 the rim of the tippler by means of a lever when desired to 

 turn it. A creeper chain is employed to return the empties to 

 the other side of the shaft for re-caging. 



There are two shaking screens with slots for the slack to 

 pass through. Water plays on them in order to lay the dust. 

 There are also two picking belts, one for each screen. The 

 slack is taken by a scraper elevator to a certain point, from 

 which another similar conveyor takes what is required to the 

 boilers, while a third takes the bulk of the slack to hopper 

 waggons. The scraper-chains are worked by sprocket wheels. 



The waggon rails below the picking belts are given a grade 

 of 1 in 80, so that they can be readily started. Instead of hav- 

 ing a travelling crane for removing the body of a waggon from 

 its under-carriage, as is commonly the case, a derrick is used. 

 The repairing shop contains two lathes, a screwing 

 machine, shears, steam hammer, punching machine, two drill- 

 ing machines, and two planing machines. The boiler plant 

 consists of six Cornish boilers, built by Hudson Bros., of 

 Clyde, X.S.W. 



