WEST WALL-SEND COLLIERY. 



281 



The electric plant consists of a small dynamo by Thomas 

 Parker Ltd., 30amp. and 105 volts, belt driven at the rate of 

 1220 revolutions per minute by a Tangye engine. It is used 

 for the electric lights during the day, and for a small pump 

 during the night. 



A Gruibal ventilating fan 30ft. in diameter and 10ft. wide, 

 provided with a Walker's shutter, is used, and is worked with 

 a 1| in. water gauge. 



The pit-head frame and pit-top is a steel structure. The 

 full skips are weighed on a Pooley's water balance weighing 

 machine, and run down grade to side revolving tipplers. A 

 creeper chain raises the empties to the proper level for caging 



Fig. 182. Travelling crane. 



again. There are two picking belts. The slack, after passing 

 through the screens, is raised by means of scrapers to a srnalJ 

 hopper, from which it is filled into the hopper skip. There is 

 no occasion to hinge the rails up which the hopper skip passes 

 to the slack box, as is usually done, for they do not get in 

 the way of the railway waggons, which are made to pass round 

 a curve. 



On the Thursday night of pay-week, each man is given a 

 pay slip with his number, name, and amount owing written 

 on it, which he brings already signed on the following day, 



