166 



COALFIELDS AND COLLIERIES OF AUSTRALIA. 



sides which works points automatically, and directs the skips 

 to one or other of the compartments ready for the upcoming- 

 cage. Just in front of the shaft is a stop between the rails of 

 each track to prevent skips going too far. This consists of a 

 hook which moves on a pin : the hook is high enough to engage 

 the axles of a skip, and is kept up by the greater weight of the 

 tail end. When desired to release a skip in order to cage it, a 

 lever worked by the foot depresses the hooked end by raising 

 the weighted end of the stop (Fig. 100). At the screen siding, 



Lever 



Lev-, 



Fig. 100. Stop. 



wooden blocks shod with iron are used to prevent trucks from 

 going too far (Fig. 101). When desired to allow a truck to 



Fig. 101. Block for Waggon. 



proceed, that block which supports the one across the rail is 

 pushed on one side. 



A dynamo by Thos. Parker Ltd. of 220 volts, 25 amp., 

 having 720 revolutions per minute, is used for electric lights 

 at the surface, pit's bottom, and flats, it also provides the 

 motive power for machinery in the shop, and a three-throw 

 pump underground. 



Signals are given along the roadways by means of electric 

 wires 10 S.W.G., and a battery of Leclanche cells. Communi- 

 cation between underground and surface is made by ordinary 

 wall telephones, with no special protection against dirt. 



On account of the low roof only ponies between 11.2 and 

 13.2 hands high can be used. These walk into the mine 

 through a tunnel, but do not come out again until it is neces- 



