260 COALFIELDS AND COLLIERIES OF AUSTRALIA. 



makes a 6ft. deep cut for a height of 4in. The Goodman 

 (Fig. 166) is more clumsy to move sideways, and requires more 

 labour. It makes a cut 7ft. deep and 4ft. wide. The picks 

 sometimes require to be changed two or three times a shift. 

 None of the machines are mounted on self-propelling trucks. 

 If the working places are close to one another, five bords may 

 be cut across per shift. All the cutting is done at night when 

 the roads are clear. Fig. 167 shows a man boring shot holes 

 with a rotary boring machine. There are two electric pumps, 

 a three-throw Worthington, and a centrifugal, both driven by 

 motors provided by the General Electric Company. The air 

 currents are induced in the mine by means of a furnace, the air 



Fig. 166. Goodman Coal Cutter on Trolly, Ready for Flitting. 



passing ^ over the fire, through the grate, and along drifts on 

 either side. The amount of air circulated is 50,000 cubic feet 

 per minute. 



Steam is generated in a Babcock and Wilcox boiler. The 

 motor is one of the General Electric Company's, built for 260- 

 250 volts, 220amp., driven by a Harrisburg standard engine, 

 controlled by a flywheel governor. 



Rhondda Colliery. 



The Rhondda Colliery belongs to Messrs. William Laidley 

 and Co., and has been in existence for ten or eleven years, dur- 



