396 
strata would have conveyed the water from the whole area, 
situated to the rise of any coal-field to such shaft, and 
rendered the sinking not only much more costly, but even 
almost impossible. As it is, however, with the water- 
channels broken up and intersected, this otherwise almost 
insurmountable difficulty is obviated, and much expense 
avoided. In sinking the celebrated Murton Winning, 
in the county of Durham, the quantity of water met 
with was most enormous, upwards of 9,000 gallons per 
minute had to be raised from a depth of 540 feet, 
and the aggregate machinery employed being equal to a 
power of 1,584 horses, boilers 39, the consumption of coal 
for which was nearly 200 tons per day. 
Fortunately, such cases are not of frequent occurrence ; the 
widely extended flow of water is intercepted by these faults, 
more properly named, perhaps, if called nature's dams. This 
is not mere theory. The celebrated Grosforth Colliery, in 
Northumberland, was purposely sunk, not on the depressed 
side of the Tynedale fault, but on the contrary ; and, after 
being sunk to the required depth, access was gained to the 
bed of coal by an horizontal gallery 700 yards in extent. 
By such arrangement the sur-charged water-bearing strata 
was entirely avoided, which was indeed the object sought 
to be attained in the arrangement. The intercepting 
character of faults is fully proved by this and similar 
instances, and the effects in deep coal-mining is very 
beneficial. And, in fact, we find in deep sinkings .that, 
in practice, water in large quantities is only found within 
a limited distance of the surface. These surface waters 
having been most effectually shut off by encasing the shafts 
with metal tubbing, a modern application, it has been 
found that deep mining is little troubled by water. Indeed, 
this is true to such an extent that, whilst in many mines of a 
depth less than 200 yards the quantity or weight of water 
