for loading ships, at
L13,000,000 sterling.

The great difficulty in working coal, should these upper seams fail, is
not only the increase of cost in sinking further down, but the increased
heat to be worked in. At 2000 feet the mine will increase in heat 28 deg.,
at 4000, 57 deg.; to this must be added the constant temperature of 50 deg. 5',
so that at 2000 feet it would be 78 deg. 5', and at 4000, 107 deg. 5' Fahr. By
actual trial on July 17, 1857, in Duckingfield Pit, the temperature at
2249 feet was 75 deg. 5'. From this it may be conceived in what great heat
the men have to work, and the work is very hard. One may fancy from this
what can be endured, but it would be next to impossible to work in a
greater temperature. I can speak upon this from actual experience, as
when down the Lady Londonderry Pit the temperature was 85 deg., and here the
men worked naked. Another great source of expense and anxiety lies in
keeping up the roof, as, from the excessive pressure, the roof and floor
are always inclined to come together, and props must therefore be used,
and these in some pits cost as much as L1500 a year. To digress for a
moment, an amusing story is told of Grimaldi, the celebrated clown, when
paying a visit to a coal-pit. Having gone some way through the mine, a
sudden noise, arising from the falling of coal from the roof, caused him
to ask the reason of the noise. "Hallo!" exclaimed Grimaldi, greatly
terrified, "what's that?" "Hech!" said his guide, "it's only a wee bit
of coal fallen down--we have that three or four times a day." "Then I'll
thank you to ring for my basket, for I'll stop no longer among the wee
bits of falling coal." This "wee bit" was about three tons' weight. A
large proportion of the sad accidents in coal-mines is caused by these
falls of the roof, which give no warning, but suddenly come down and
crush to death those who happen to be near.

MODE OF WORKING.

The cost of working having thus been given, I wish now to lay before you
an explanation of the method of working and bringing the coal to the
surface. It may not be uninteresting to mention how many men are
employed in this work, as the number is very large. Coal was not
formerly excavated by machinery, but it is so now, and therefore hands
must be had. The number of men employed in the mines of county Durham in
1854 was 28,000; of these, 13,500 were hewers, winning several thousand
tons of coal daily. Of the remainder, 3500 were safet