REMARKS ON THE WASTE IN COAL MINING.

BY R. P. ROTHWELL, M.E.

AT this our first meeting I beg to call the attention of the members of our Institute to what is certainly a question of the greatest possible importance to the industries we represent; and more particularly to the welfare of the coal and iron trades: I refer to the enormous waste of coal in mining and in its preparation for market, as now practised in our anthracite coal-fields. It is a fact which many of you can certify to, that we are wasting fully one-half of all the coal in the veins we are now working, and there are cases, which might be mentioned where this proportion, immense as it is, has been greatly exceeded.

The popular belief that our deposits of anthracite coal are "practically inexhaustible," is very far from being founded on facts. On the contrary, supposing the present rate of increase in the production to be maintained, it is probable that a maximum yield for our coal-fields would be attained in about fifteen years; there are in fact some of our smaller basins where the principal veins are nearly exhausted and the production has already attained its maximum. There are others, again, where the depth attained—and it must be borne in mind that we commenced working at the surface outcropmoderate though it is (scarcely ever reaching eight hundred feet), has so increased the cost of mining as to imperil the capital invested, and though it requires but little foresight to predict the time when the difficulties of mining will be very considerably increased by reason of the greater depth, greater quantity of water, fire-damp, and other fruitful sources of cost, yet, ignoring these recognized facts, we continue to waste more than one-half of the coal where it is obtained with the least danger, expense, and trouble, that is, near the surface—either above water-level or at a moderate depth below it.

The inspection of almost any accurate mine map will satisfy you that, on an average, we leave fully one-third of the coal in the ground as pillars to support the roof; in some places more than one-third thus remains, while it is very rare that less than onequarter is left. In almost every case this coal is absolutely lost, for it will very rarely pay to reopen gangways and lay roads to it after that portion of the mine has been abandoned. Is it necessary in all cases to support the roof, and where it is, may not some artificial

support, stone or iron-for wood appears too perishable-be found cheaper than coal at certain depths? But, in addition to this source of waste, we have another, which, though not so great in per cent., yet attracts much more attention, and is in reality much greater than has generally been supposed, that is, the loss in breaking up the coal for the market. The mounds of "culm," or "coal dirt," which we meet with at every step in our mining districts, testifies sufficiently to the amount of this waste, and the loss of coal from these two sources amounts to fully as much as our shipments to market, or say about 15,000,000 tons per year at present! This is a condition of things which, as engineers, as individuals interested in the industries whose welfare our organization is intended to advance, or as citizens, having the prosperity of our country at heart, we should not allow to continue till we had exhausted every available means for improvement.

The question naturally forces itself on us, is there such a waste in coal mining in other countries, where veins as large, as highly inclined, and otherwise as difficult to work as ours, are mined? and if not, cannot their systems of mining, or some modification of them, be applied here to advantage?

The system of leases under which the operator pays for coal shipped, but not for coal wasted, and for the larger sizes frequently a larger royalty than for the smaller sizes, greatly aggravates the evil. When the leases are, moreover, for short periods, the combination of conditions is most mischievous. It then makes no difference to the lessee how much coal is wasted or left in the ground. His efforts are directed to getting to market as much coal of the most salable sizes in the given time.

The proper plan, in my estimation, would be to have the leases so drawn that the operator would pay for coal a certain sum per foot in the vein, instead of paying by the ton shipped. I think, also, that the breaker system could be improved. In fact, in the breaker which the members have visited (Mr. Swoyer's), provision has been made for separating at the outset the coal which does not need to pass the rolls.

Mr. Rothwell concluded with a recommendation that a committee be appointed to consider this subject, and report at a future meeting of the Institute.

DISCUSSION.

MR. SWOYER showed that the cost of land on the surface inter

feres with the long-wall system. He explained that in the Wyoming region the tendency was towards permanent leases, so that the tenant regarded the coal as his own, since he had, in fact, bought it, but paid in instalments instead of cash down. He complained of the whims of consumers as to uniform sizes of coal, asserting that this was the only reason of the great investment of capital, and the great waste of coal in the breakers. Combined with short leases, this state of things produced much mischief. If he had a short lease of a coal mine, and, for some reason, small sizes were to bring a relatively high price in market, he would naturally convert all his coal to small sizes, in spite of the actual waste, because of the present financial profit. Under a long lease, on the other hand, he could afford to consider the ultimate value of the coal. He thought the best arrangement between owners and operators would be to pay the royalty on the coal as it was raised, before it was prepared.

MR. HOFFMAN reviewed the paper of Mr. Rothwell at some length. He thought it possible to retain the pillar and chamber system of mining. It might come to be a serious question whether the small villages over coal mines were worth the reservation underground of so much coal to support them. He was not aware of a higher royalty being paid for one size of coal than another. He thought the general adoption of long leases would improve the economy of coal mining more than any other simple remedy-the operator to mine so many tons per year, and observe proper rules of working.

MR. ROTHWELL replied that in the Wyoming region the lessees often actually paid less royalty for chestnut and the smaller sizes than for lump or steamboat coal.

MR. RAYMOND called attention to the difference between actual and economical exhaustion of mines, as illustrated in recent discussions as to the duration of English coal mines. Economical exhaustion might take place long before the mineral was all extracted, simply by reason of increased expense. It did not follow, because of the abundance of coal in the anthracite regions, that a reckless waste of it would not bring about in many cases a premature economical exhaustion. Just as soon and as long as a mine could not be profitably worked, it was practically exhausted. Moreover, mineral wealth was given to a country but once. Such resources would not grow again, like products of the soil. With regard to the particular case under consideration, he had no doubt the Council would appoint a committee to consider it, and report deliberately

upon it. Hasty theoretical recommendations were of little benefit. It was clear that we must suggest something feasible, and not commercially ruinous, to our friends the operators, or else our talk about their waste would be fruitless. He had been a strong partisan of the long-wall system; but he must frankly admit that he saw many difficulties in the way of its employment in large "pitching" seams, and in localities where, of several workable seams, the lowest was at present working, because it was, by reason of greater thickness or better quality, or any other circumstances, the most profitable. Villages on the top might in time decay, by the suspension of the mines which support them in a double sense. Cases of the sudden rise and fall of mining towns in the West were given. On the whole, the present system of mining in the anthracite regions, bad as it was, was a system hanging together, and much study would be required to suggest practicable amendment.

BETHLEHEM MEETING,

AUGUST, 1871.

PRELIMINARY REPORT OF THE COMMITTEE UPON THE WASTE OF ANTHRACITE COAL.

BY ECKLEY B. COXE, CHAIRMAN.

AT the first meeting of the Institute, a paper was read by Mr. Rothwell, calling attention to the importance of at once considering the great waste of anthracite coal under the present system of mining and preparing that fuel for market, and a committee was appointed to examine and report upon the method now in use.

About the time the committee were selected, a general resumption of work, after the long strike, took place in the coal regions, and the members of the committee have not in consequence had as much leisure to devote to the study of the question as its importance demands.

In the present preliminary report we shall merely sketch out the plan which we propose to pursue in our investigations, so that when our fellow-members are called upon to assist us in our work by furnishing statistics, etc., they may understand more clearly for what object our inquiries will be made.

As one of the most practicable methods of obtaining the information requisite for an intelligent consideration of our subject, we propose to send, from time to time, to members and others interested in the mining of anthracite coal, printed sets of questions relating to points under consideration. We would here impress upon our fellowmembers the importance of filling up these papers as far as they can from their own knowledge. We would, of course, wish each question to be answered as fully as possible, but we do not expect every one to answer them all. One question well answered would be of more use to us than the whole paper filled with answers, many of

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