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no inflammable gas ; whilst beyond this depth, little water is 
met with, but a greatly increased quantity of gas. This 
will materially affect the future deep coal-mining of this 
country. 
BANDS IN COAL-BEDS. 
Coal-mining is materially affected by the intercalation 
in the coal-beds of earthy matter, technically Darned bands. 
These are not co-extensive with the bed of coal, but begin by 
a mere smooth parting or division of the bed, gradually 
increasing, I believe, generally, in a given direction in all 
the beds of coal in any coal-field, until the bed becomes 
divided into two distinct beds, many feet apart. Undoubtedly, 
some coal-seams are very persistent, extending over many 
square miles ; but even these are frequently found to be 
divided. Beginning from the north, the Silkstone and 
Barnsley beds are frequently thus divided in passing south- 
ward through Derbyshire. In the north of England scarcely 
a bed is known but is thus affected. 
The High Main, or original Wallsend Seam, is divided by 
the Heworth Band, gradually thickening to the south, and 
ultimately forming two distinct beds. The gray seam of 
Cramlington is similarly divided as it passes southward; 
and the far-famed and unequalled Hutton Seam is also 
divided more than once as it follows in the same direction, 
forming distinct beds. There is scarcely any bed of coal 
that is not similarly affected. The Ten Yard Seam of South 
Staffordshire is divided into nine distinct seams ; in North 
Staffordshire by 420 feet of sandstone and shales, the whole 
change taking place in 4 or 5 miles. In the Warwickshire 
coal-field, five distinct coal-seams become united by the 
thinning out of 120 feet of sandstone and shales, forming at 
Wyken, near Coventry, one bed 26 feet in thickness. 
The fact that it is frequently, if not universally, found 
that the lower portion of a coal-bed thus divided by a band 
