328 COALFIELDS AXD COLLIERIES OF AUSTRALIA. 



wide by 7ft. high, and timbered, thus forming another jig. 

 This enlarging of the end cut-throughs is termed stripping the 

 jig, and is done by two rnen, one working 011 either side. A 

 shoot is placed at the bottom of this jig, and the coal allowed 

 to roll down by gravity, but when the stripping is completed, 

 rails are laid, and a place prepared at the top for the brake 

 drums. 



When the bords in a section have been driven, men com- 

 mence to drop the pillars and top coal. The pillar imme- 

 diately below the upper level is left as a support., but the top 

 coal of the first bord is dropped. Then, commencing a chain 

 from the jig instead of 15 yards, so as to protect the jig, the 

 pillar is taken out in four foot strips from the bord below, for 

 a height of seven feet. When eight yards have been worked, 

 several of the props of the first strip and the continuation of 

 them in the bord are drawn, only just sufficient being left to 

 temporarily support the roof. The roof is then shot down by 

 placing blasting powder in holes made nearly vertically over- 

 head. After the first step has been worked, there is always a 

 free end to shoot against. A shot in the lowest portion of the 

 strip often fetches down the lot, but if it does not, more than 

 one hole has to be bored. If the roof is rotten, then the powder 

 is tied on to the timber, and the prop blown down, or the prop 

 may be rammed down by a long pole. It is intended to always 

 keep three rows of props at least between the second working 

 and the working face of the pillar, but sometimes the shooting 

 may fetch down the roof up to the face, in which case one has 

 to start on the pillar as if commencing afresh. The coal won 

 from the pillars slides down to the track in the bord, when it 

 is filled into skips. As the roof will not allow the full width 

 of a pillar to be extracted, a rib is left, when signs of weak- 

 ness occur, but this is sometimes fetched down when dropping 

 the roof. The stone overhead is conglomerate, and generally 

 stands well, but sometimes falls with the top coal. It much 

 of the roof falls, they do not bother to sort out the coal, but 

 leave it where it falls. The bords are worked forward, and the 

 face at the top is in advance of the bottom, as this gives a 

 better grade for the miners to reach their work. The men 

 arrange a stand by placing a plank under and over two adja- 

 cent arid parallel props, the projecting end serving as a sup- 

 port to stand or sit on (Fig. 206). If the coal of a pillar shows 

 signs of being tender, it is held by slabs resting against 

 props placed close to the pillar, and so as to prevent the posts 

 from falling, long sticks known as "needle timber" are placed 

 so that one end rests against the foot of a prop and the other 

 is let into a hitch in the roof, so arranged that it is a little 

 higher than the end resting against the prop. The pillars 



