CHAPTER VII. The Mining Plant at the Surface. In no feature do anthracite collieries differ from each other as much as in the arrangement of the plant above-ground. This is due in part to generic differences in the structures that go to make up the plant, and in part to the topography of the surface on which these structures are erected, but principally because the mine superintendents and engineers throughout the region, apparently have not sufficiently appreciated the fundamental principles by which the best arrangement of all such plants should be determined. At some of the more recently opened collieries,-notably those of the Lehigh Valley Coal company,—the arrangement of the plant is all that can be desired; but at nearly all of the older collieries, and not a few of the newer openings, the various structures composing the plant seem to have been located at random, and with no view to the harmonious working of the whole as a unit. However, at the older collieries this has doubtless been brought about by the remodelling and enlargement of old plants, and the addition of new structures, to meet the requirements of an increased output. At an anthracite colliery the plant at the surface usually consists of the structures enumerated below, and the object to be attained in determining its arrangement, is the harmonious working of the whole as a unit without destroying the individuality of any of its members. Thus we ordinarily have: 1. The Head-frame, or, if weather-boarded, the Headhouse. 2. The Winding Engine, Drums, etc. 3. Boilers and coal-bins. 4. Breaker Engine. 5. Breaker. (105 AC.) 6. Culm or dirt, or waste and rock banks. 7. Dirt plane? 8. Pumping Engine. 9. Fan. 10. Breaker Engine. 11. Breaker Hoisting Engine? 12. Railroad tracks. It is necessary to refer first to the old plan of building. the breaker over the shaft. When this plan is adopted, the breaker, head-frame, and engine-house (?) are merged into one, and the cars are raised directly to the top of the breaker. The first cost of such a plant may be less by from five to ten thousand dollars than a plant in which these are erected as separate structures, and a saving in the cost of operating such a plant is also effected. On the debit side of the account, however, we have created a risk that may at any time wipe the whole structure out of existence, and at the same time greatly injure or ruin the mine. When this plan is adopted the engine-room is usually, if not inside of the breaker, a contiguous structure, and as in this room, cotton-waste and other oily and extremely inflammable material may always be found, the risk of fire is by no means small. When the engine-room is in the breaker, the risk is greatly increased by its location, and by the probability of cotton-waste being thrown or blown by the draught into out-of-the-way places where spontaneous (?) combustion may occur. In addition to these probable causes of fire, there are within the breaker itself many possibilities of conflagration, the principal of which are hot journals, oil, and cotton-waste, and in addition, the risk from incendiarism. The damage done to the shaft and the probability of a mine fire resulting from the burning of the breaker, in addition to the risk of great loss of life in the mine under such circumstances, are sufficient reasons why such a plan should not be adopted, but there are others equally if not more forcible, and these may be briefly summarized. In gaseous mines such an arrangement is especially dan gerous, as in the event of a serious explosion in the mine, the breaker may be greatly injured if not destroyed, and many of the breaker hands (numbering from one to two hundred) killed and wounded; again, in case of a mine fire involving the shaft, or of fire in the shaft alone, the destruction of the breaker is nearly certain. In addition to the risk from fire and explosions, the damage that may result to the breaker and the risk to life from any accident (whether from breakage or over-winding) to the winding machinery is not to be under-estimated. Notwithstanding all these risks incurred by erecting the breaker over the shaft, many private operators and incorporated companies, adopt this arrangement and accept the accompanying risk, rather than incur the additional expense entailed by constructing and operating the breaker, head-frame and engine-house as separate and independent structures. A compromise between these two plans has been adopted by the D. & H. Coal Co., as shown by Page Plate 43 in which the head-frame is built some little distance from the breaker, and connected with it by a trestle-work. The cars are raised at once to the level of the breaker-dump and run over the trestle to the tip. This design is free from most of the objections that pertain to that in which the breaker is placed directly over the shaft, but the risk is greatly increased by housing in the head-frame and trestle. In case of a mine fire involving the shaft this head-house and the covered trestle would act as a flue and draw the fire over into the breaker, and in case of fire in the breaker the head-house would probably be involved through its connection with the covered trestle. To reduce the risk to a minimum the head-frame and trestle should be built of iron, or of large heavy timbers, (roofed in if considered absolutely necessary) without weather boarding of any kind,-in other words an open skeleton structure that will not readily burn. At collieries at which the coal is raised through slopes, these objections do not apply, as the breaker is then placed in front of the slope-mouth; the main structure standing fifty feet or more from the opening, and connected with it |