HERMITAGE COLLIERY. 



lOo 



causes the jockey to turn on its vertical axis, and in doing so 

 the fork pinches the rope, thus gripping it firmly. The weight 

 of the rope 011 the coal also adds slightly to the hold. The 

 grip of a jockey is not strong enough for more than one skip 

 at a time. The endless rope is not spliced, but has its sections 

 connected together with Gin. sockets, the rope being swelled 

 in the socket by driving a steel wedge in the core. The haul- 

 ing engine was made at the Atlas Works, Sydney, and is a 

 slide valve, link motion, geared G to 1. The grip wheel has 

 one V-shaped groove. The tension pulley is mounted on a 

 trolly (Fig. 41), and runs on a track down hill at an angle 

 of 15 degrees. 



Fig. 42. Conveyor. 



Small doors are left in the stoppings now and again, so 

 that repairing timber can be passed through to the return air- 

 ways. Sliding doors are used for splitting the air. An Inger- 

 soll-Sergeant air compressor, having one steam cylinder, 12 

 by 14iii., and one air cylinder, which takes air in through the 

 piston rod, is used for power to drive two pumps; one a Blake 

 with a double ram one at either end, the other a Snow 

 double-acting four-plunger pump. After passing over one of 

 Pooley's weighing machines the skip is run into an end 

 tippler, the hooks of which hold the skip by the two front 

 wheels, not by the front axle; the band brake is worked' by 



