332 



COALFIELDS A^XD COLLIERIES OF AUSTRALIA. 



but are dogspiked to the sides of the sets. There is no occasion to 

 allow spaces between the rails for expansion and contraction, 

 as the temperature is fairly uniform throughout the year. The 

 rails are connected with fish-plates, and occasional rails have 

 holes in their flanges, through which they are spiked to the 

 sills and thus prevented from working bodily downwards. The 

 tunnel cage is a double decker (Fig. 208) ; the top deck is 

 covered in on top and at ends, and is used for men and horses, 

 as well as for skips. When horses are on board, wooden sides 

 are put on. Two skips are on each deck, placed side by side, 

 and kept in position by both axle catches and finger bars. When 



Fig. 208. Double-deck Tunnel Cage. 



skips are to be run ofi: the cage, the finger bars are thrown 

 on one side and the axle catches propped up. The skips are run 

 in at the side of the cage on to angle iron rails. As all the 

 uncaging takes place at one spot, when the full skips have 

 been run off the upper deck, and the empty skips run on, the 

 enginedriver has to raise the lower deck into position. Under 

 the lower deck is a water tank. This is emptied automatically 

 "by a fixed finger that strikes the lever attached to the valve of 

 the tank. The wheels of the cages have double flanges, so as to 

 h(4p them keep the rails. Ten men travel in the covered 



