LITHGOW VALLEY COLLIERY. 



101 



in the coal from the outcrop. The coal is extracted by the 

 pillar and bord method. The neck to a bord is made five yards 

 wide for two yards, and in the next four yards it is gradually 

 widened out on either side to the full width of the bord. 

 namely, eight yards, or room for two men. The coal is found 

 to stand better than when widened out suddenly. 



The ventilation is carried out by means of two furnaces, 

 one in each return airway, which terminates in a short stack. 

 An air passage between the furnace and coal prevents 

 the latter from catching alight. As this passage has no 

 connection with the stack, no air can be drawn through them 

 for ventilation purposes. The stoppings are of brick, built up 

 of two rows of stretchers side by side, which break joint, and 

 are bound together with two rows of headers in the total 

 height. The top of the stopping is only one brick thick. 



The hauling is now done by an endless rope, which rests in 

 jockeys above the skips. The life of a tail rope is less than 

 that of an endless rope, as it is never out of the mine, and is 

 subject the whole time to moist air and gases, besides, it 



rfl 



Fig 38. Jockey. 



winds up over itself on a drum, and so becomes crushed. The 

 oldest part of the present endless rope is> four years old, but 

 two lengths have been added to it since. Twenty-^ouncl rails 

 are laid, on which the skips run singly, not in sets, at a speed 

 of two and a-half to three miles per hour. Rollers are placed 

 between the rails for the rope to rest on when not lifted oil 

 by the jockeys. This system is only good for straight roads 

 with light, even grade, as is the case in this mine. The skips 

 are released from the rope automatically, so no clippers-on or 

 clippers-oif are required. If a skip gets off the track, the 

 rope is lifted oui of the jockey and just runs on the top of the 

 coal, doing no great harm. Two jockeys are used (Tig. 38), 



