102 



CK)ALFIELDS AND COLLIERIES OF AUSTRALIA. 



both being- placed at the back of the skip, for at the other end 

 is a door, through which the coal is unloaded (Fig. 37). The 

 longer jockey is used when the skip is full, so as to keep the 

 rope above the coal. The shorter jockey is used when returning 

 empties, for if the longer one was employed, as the empty skip 

 is light, the greater leverage would tend to pull it over. The 

 endless rope being worked above the skips instead of below, 

 as is usual, it is easily raised out oii the jockey automatically 

 by causing it to pass over a pulley, which takes the weight off 

 the jockey, so there is no fear of the skip being dragged to 

 the "cundy" or "conduct," where the rope passes under the 

 roadway. For branches, the rope will be led into different dis- 

 tricts, connections being made at the flats. The hauling engine 

 is a single cylinder on the second motion. A diagram showing 

 the method of taking up the slack of the rope is shown in Fig. 

 39. Iron cross-sprags are used to place between the spokes 

 of the skip wheels when there is so little room that the 

 sprags must be pushed in a certain distance to prevent them 

 from coming in contact with other objects ; the guards uiv 

 also useful when the skips are travelling fast, as there is then 

 no danger of the boys pushing them too far in their haste. 



A Brush motor, 450 volts, 15 amp., 1420 rev. per min., is 

 used for working a pump, electric lights, and a' corn cracker. 

 The electric signals are worked by a battery, bare galvanised 



Fig. 39. Method of Taking up Slack Hope. 



iron wires being used so that they can be brought in contact 

 when desired to signal anywhere along the roadway. Besides 

 the two signal wires, there is a telephone/ wire and two pump 

 cables. The button insulators are screwed to a piece of wood, 

 which is nailed to wooden plugs driven into holes in the roof. 

 The pump is a three-throw plunger, driven by a dynamo pro- 

 ducing 350 volts, 13.2 amp., with 1230 r.p.ni. 



After passing through the screens, the slack is raised to a 

 storage, bin by a bucket elevator; it is 1 then conveyed along a 

 trough by scrapers, and is distributed to different parts of the 

 bin by drawing a slide from a spout to let it down where re- 

 quired. This is worked by a rope from the haulage engine, 





