THE WALL AR AH COLLIERY. 



245 



means of tunnels. "B" is the older and "E" the newer 

 pit, and most of the plant is situated at the mouth of the 

 latter. The underground workings of the two pits are con- 

 nected. The haulage at both pits is an engine plane, but at 

 the "E" pit they are preparing to instal the endless-rope sys- 

 ieni for the main haulage, though the engine-plane will still 

 be used for the first section, where the roadway is considerably 

 curved. A set consists of 15 skips. The rollers to support 

 the rope between the rails are of iron bark timber, turned with 

 a shoulder at either end, which supports one edge of the iron 

 rings that bind them, while nails on the outside prevent the 

 rings from coming off. About 60 strong horses, from 14 to 

 15 hands high, are employed at the mine. 



The coal is worked by bord and pillar. Bords worked by 

 pick are 8yds. wide, the pillars between being 12yds. wide; 



Pig. 154. Sullivan Electric Chain Machine, showing "pan" 

 detached and in position for starting a side cut across the 

 face. 



but those worked by machines are 12yds. wide, and the pillars 

 between 14yds. Very little pillar extraction has been carried 

 out, as there are so many places on the surface where water 

 flows, and the working's being shallow, should the roof cave 

 in, the amount of water admitted to them might caiise con- 

 siderable inconvenience and expense. Since there was some 

 divergence of opinion as to which was the best class of 

 machine to employ for coal cutting, different mines favouring 

 the particular type they had adopted and were accustomed to, 

 at this colliery, four kinds of coal cutters were tried, namely, 



