Author Description

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1861 Excerpt:...this coal-field. Resources. In estimating the resources of this coal-field I include only the workable seams of the Middle Coal-measures; the coals of the Gannister series, though frequently of good quality, being too thin to be worked at depths much greater than 300 yards. 1. Area of coal-field (not including that por tion underneath the Magnesian Limestone) 760 square miles, 2. Greatest thickness of productive coal measures (from the Ackworth rock above the Shafton coal to the Low Moor coal)... 2,500 feet. 3. Average number of workable coals above 2 feet, 15; giving a vertical thickness of coal.......... 4fi „ 4. Total original quantity of coal (corrected for denudation)...... 17,656 millions of tons, 5. Deducting 14th for the quantity worked out, and l-4th for waste, &c., we obtain for future use (about).... 8,800 „ „ 6. The area, overspread by Permian (Magne sian Limestone) and Trias, under which several of the workable coals lie at a depth within 4,000 feet, is about 400 square miles, containing.... 12,000 „ „ 7. From this deduct l-3rd for loss, leaving for future supply...... 8,000 „ „ 8. Total available quantity under 4,000 feet in depth is therefore 8,800 + 8,000.. 16,800 9. This at the present rate of consumption would last for 1,340 years. This result shows to how limited an extent the great resources of this coal-field are as yet developed. In fact we may in some parts traverse large districts well stored with coal, where not one colliery is in sight, and the fact becomes more apparent when we recollect that the great tract occupied by Magnesian Limestone and New Eed Sandstone--under which the whole of the beds of coal are known to descend--is as yet pierced only by five collieries, producing, as I am...