66 
THE GEOLOGIST. 
the empty spaces, h, as the coal is extracted. And a sort of bed is 
thus made to receive the descending roof. It is stifling work in these 
thin seams when the poor hewers have to he on their sides and ply 
their picks against the black wall in face of them, with a yellow 
Fig. 6.— Plan of worked-out iline. 
a, the galleries with their walls of sohd coal; B, C, the "goafs," or worked-out spaces filled 
with shale and rubbish ; i), shaft ; b e, dip-head level. 
candle flaring in the one hand, (or a Davy,) the elbow resting in a 
hole cut to receive it, and the whole man sweating in a hot atmosphere 
for hours together. It is a heavy price to pay for comfort above ground. 
But they do not murmur ; and a good hewer will clear eighteen 
shillings a week, after paying for his candles, tools, &c. ; while the 
overmen receive twenty-five to thirty shillings. 
The thick coal of Stafibrdshire was formerly mined on the " pillar 
and stall" system ; and Mr. Warington Smyth has given a graphic 
picture of a " side of work in the ' thick seam,' when a large fall of coal 
is brought down from the dusky heights of that lofty chamber. The 
thunder of the falling masses, which seem to shake the solid earth, 
contrasts fearfully with the dead silence that ensues. The hardy 
colliers scarce break it by a whisper, while in suspense they listen for 
the slightest crack which might portend a further fall." But the 
enormous height of this coal-chamber, often thirty feet, was of itself 
a source of danger; and the pillars required, and which must be all 
waste, so large, that it is now found profitable to work it in " long- 
wall" method, a half or more of the seam at a time, beginning at the 
top. By this means they get all or nearly all the coal — about thirty 
thousand tons to an acre. They used to get but sixteen thousand. 
There are four hundred and twenty collieries in this district alone. 
About one third of the coal they raise is expended in their furnaces ; 
(for near a million tons of ironstone are raised in this field annually, 
besides the coal formerly mentioned, page 10). About half as 
much is sent from other places ; and a year or two back this quantity 
produced six hundred tliousand tons of pig-iron from sixty-four 
