SALTER — A CHRISTMAS LECTURE ON COAL. 



65 



to support the roof, and gradually driving the galleries or stalls 

 forward, up the slope of the mine. 



The coals are brought down the galleries, which have each a tram- 

 way laid in it, in small wheeled cars, which either carry the skips or 

 are themselves detached from the train, hauled up, returned empty, 

 and again wheeled up by the "putters," or boys employed for this 

 purpose. Ponies generally draw the loaded cars in lines along the 

 diphead level to the mouth of the drawing shaft ; and these ponies, 

 sleek and well-fed, live in the warm mine and like it. They learn to 

 hold fcheir heads low, for there is never too much space in a coal 

 gallery ; and if we would imitate them, we should escape many 

 bumps through life. 



When all the galleries are cut, then they begin to thin the 

 "posts" — and this is a work of some little danger. Not only is the 

 roof inclined to come down on the miners' heads, but the floor often 

 bulges up beneath their feet. Such a disturbance of the ground, 

 arising from the great pressure above, which forces down the pillars 

 into the clay beneath, is called a " creep." It has an odd effect on 

 the buildings over the colliery. They begin to fall sideways out of 

 the perpendicular; square windows take a lozenge shape ; doors, &c. 

 will not open, being jammed at one corner. Ceilings fall, bit by bit, 

 upon the inmates ; and altogether a " creep" produces unpleasant 

 feelings for all concerned. But it cannot be helped — the black stores 

 below are worth more than the buildings above ; and, therefore, they 

 must go the way of all buildings. 



The process of thinning may begin at one corner, a, (the furthest 

 from the shaft,) before all the galleries are finished ; and when a good 

 many of the "posts" are thinned as much as they will bear, they extract 

 even these, substituting wooden posts for coal ones. The space then 

 looks like a forest of dead props, among which you may easily lose 

 your way ; and, as these decay, down comes the whole mass, slowly 

 but surely, till the roof and floor meet in a broken irregular mass. 

 The hollow space with its ruin of shale and sandstone — of sound and 

 decaying props, is then shut off from the other compartments of the 

 mine. No ventilation is further given to that quarter, called a 

 " goaf," and foul gas and tar- water, and every abomination, may 

 collect there till time shall end. It is a sort of Tophet. 



There is another way of working, much used in thin seams and 

 small collieries, and universally preferred in Scotland. It is " long 

 wall" working. In this method the galleries are driven (as before 

 from a dip head level) parallel to one another the full extent of the 

 mine, but not near together, and the coal between the ways is then 

 worked out bodily ; — small entries being made through the wall, and 

 all the intermediate coal " got" out, enough only is left along the 

 sides of the ways to ensue the safety of the latter. 



Our diagram shows a piece of this sort of work. (Seep. 66). 

 The rubbish, (roof,floor, &c.,) which must be got out in the main ways 

 with the fuel in thin seams of coal or ironstone, (for ironstone is got 

 in almost every coal pit,) need not be taken away ; but is filled into 

 VOL. iy. I 



