THE LOWER COAL MEASURES. 249 
The coal was opened on the dip, and consequently the mine was 
troubled with water from the first. Water cannot be left in the clay 
floor of the coal without causing it to slack and throw the track, and 
interfere with the drainage. The bottom bench is generally counted 
the best portion of the seam, but there are no facts of analysis to 
establish this view. 
The same structure characterizes the seam in the Empire mine, 
No. 2, which has an expensive plant, one-half mile south of Dell Roy. 
A greater thickness of coal than that last reported is, however, found 
at this mine. In the main entry a noble body of coal, fully 6 feet in 
thickness, is shown for a short distance, but there is also shown here 
one of the rapid and disastrous reductions of the coal, which unfortu- 
nately constitute a characteristic feature of the seam in all its extent. 
The seam in this field always gives way in the upper benches when its 
thickness is suddenly reduced, the bottom bench seldom being at all 
affected. The average thickness of the coal in the Empire mine, No. 2, 
was 4 ft. 10 in. in the rooms where it was worked, but it is counted a 
5-feet seam. Horsebacks were so often met, and were of such large 
extent, that mining was suspended here fora time. It has, however, 
been resumed, and is to be carried forward on a large scale. 
The general structure of the seam is shown in the following figure : 
FIGURE MLV 
STRUCTURE OF DELL ROY COAL, EMPIRE 
INE, N&Z. 
lales, Wilma Benes eh ihe tas is 
Shales Black... == 
Coal vatecvupted, witha 
Vigadvers siamad 00h veins 
invegulas 
FOE ae en 
Goal ——-_—-_--------- 
The disappointment arising from the unsteadiness of the coal, when 
this flatter fact is first discovered by the operator, often leads to a 
temporary undervaluing of the seam, but the fact remains that in spite 
of its frequent “ wants,” the Upper Freeport coal is still one of the most 
valuable seams of the State. 
“ 
