In the act of 1885 it is provided that “no inflammable structure other than a frame to sustain pulleys or sheaves shall be erected over the entrance of any opening connecting the surface with the underground workings of any mine, and no breaker or other inflammable structure for the preparation or storage of coal shall be erected nearer than two hundred feet to any such opening.” This was for the purpose of preventing, if possible, such lamentable disasters as those of Avondale and West Pittston. The results of this legislation in providing greater security to the employees in mines is invaluable. Formerly it had been the custom to build not only the shaft-house over the opening into the mine, but the breaker itself, wherever there was one, was usually erected over the mouth of the shaft. This was convenient and economical, since the coal could be hoisted directly from the mine to the top of the breaker, without the delay of a horizontal transfer at the surface of the earth. Many of the shaft houses and breakers that had thus been built at the time of the passage of the act are still in operation, and will so remain until the time of their utility is passed. But all new buildings are erected in accordance with the law.

THE SLOAN COAL BREAKER, HYDE PARK, PA.

At the mouth of the shaft heavy upright timbers are set up, inclosing the opening. These are united by cross-beams, and the whole structure is well braced. In this head-frame are set the sheaves, at a distance from the ground of from thirty to fifty feet, although, when the entire surface plant was under one cover, they were set much lower. These sheaves are huge upright wheels sixteen feet in diameter, over which the ropes pass that connect with the cages. A sheave similar in form to the bicycle wheel is now coming rapidly into use; it is found to bear a greater strain in comparison with its weight than does any other form.

The hoisting engine must be in the immediate vicinity of the shaft, and the rooms for this and the boiler, furnace, and pump are usually all under one roof. The iron or steel wire ropes extend from the sheaves in the head frame to the drum in the engine-room, around which they are coiled in such a manner that as one is being wound up the other is being unwound. Therefore as one carriage ascends the other descends by virtue of the same movement of the engine.

Since the breaker may receive coal from two or more openings it must be so located as to be convenient to both or all of them. If the ground slopes sufficiently the breaker may be so built that its head will be on a level with the head of the shaft. This will save breaker hoisting. When coal is brought out by a slope the track and grade of the slope are usually continued, by an open trestlework, from the mouth of the opening to the head of the breaker. Wherever it is possible to do so, the loaded cars are run by gravity from the mouth of the opening to the breaker, and the empty ones are drawn back by mules. Sometimes they are hauled both ways by mules, and sometimes a small steam locomotive engine is employed to draw them back and forth.

The coal breaker is an institution that is peculiar to the anthracite coal fields of Pennsylvania. Its need was made manifest early in the history of anthracite mining, its development was rapid, and it has now come to be wholly indispensable in the preparation of anthracite coal for the market. It is very seldom indeed that one sees this coal in the shape and size in which it was mined. All anthracite coal for domestic use is now broken, screened, and separated into grades of uniform size before being placed upon the market, and this work is done in the coal breakers.

Previous to the year 1844 these breakers were unknown. Several experiments had been made in the matter of breaking coal by machinery, but there had been no practical results, and the breaking still continued to be done by hand. In that year, however, a breaker after the modern plan was erected at the mines of Gideon Bast, in Schuylkill County, by J. & S. Battin of Philadelphia. It was started on the 28th of February, 1844. There were two cast-iron rollers in it, each about thirty inches long and thirty inches in diameter, and on the surface of these rollers were set iron teeth or projections about two and one half inches long and four inches from centre to centre. These rollers were placed horizontally, side by side, and were so geared that, as they revolved, their upper surfaces turned toward each other, and the teeth on one roller were opposite to the spaces on the other. These rolls were afterward improved by being perforated between the teeth, thus presenting less of solid surface to the coal, and causing less crushing. Another set of rollers was afterward added, being placed above the first set, and having the teeth larger and wider apart, so that large lumps of coal might first be broken into pieces small enough to be crushed readily by the lower set. After the perfecting of the rolls came the perfecting of the screens for the purpose of separating the broken coal into grades according to size. Before the introduction of coal breakers a hand screen was used. This screen was set in a frame, was cylindrical in form, and was slightly inclined from the horizontal. It was turned by a crank at one end, in the manner of a grindstone. The screen placed in the breaker was of much the same pattern, except that instead of being from five to eight feet long the length was increased to twenty feet, and the diameter correspondingly enlarged. Mr. Henry Jenkins of Pottsville then invented a method of weaving thick wire into screen plates about three feet wide, having the proper curve. These curved plates being joined together formed the necessary hollow cylinder. These separate plates are called jackets, and when one of them wears out it may be taken from the cylinder and replaced, with but little trouble and delay. The screen is set in heavy framework, and is inclined slightly from the horizontal. The first segment at the upper end of the screen is made of wire woven into a mesh so fine that only the smallest particles of coal will pass through it; the mesh of the next segment is larger, and that of the next larger still. The screen may contain from two to five segments in its length. Now the coal, being poured in on top of the revolving rolls, comes out from under them broken into small pieces, and passes immediately into the upper or highest end of the hollow cylindrical screen as it would pass into a barrel. But, as the screen revolves on its axis, the finer particles of coal fall out through the fine mesh of the first segment, and are carried away in an inclined trough, while the rest of the coal slides on to the next segment. Here the next smallest particles fall through and are carried away, and the process is continued until the lower end of the screen is reached, out of which end all the coal that was too large to pass through the mesh of the last segment is now poured. It will be seen that by this means the different sizes of coal have been separated from each other and can be carried by separate shutes to the loading place. This is the principle of the rolls and screens which are the main features of every coal breaker, though each breaker usually contains two or more sets of rolls and from eight to twelve screens. The Woodward breaker recently erected near Kingston, Pennsylvania, has six pairs of rollers and twenty screens. Some of these screens are double; that is, they have a larger outside screen surrounding the smaller one, and the coal that passes through the inner screen is caught by the outer one and again divided by means of a smaller mesh.

Before the days of breakers and screens coal was sent to market in the lump, as it came from the mine, and it was generally broken and prepared for use by the consumer. But when the separation of coal in the breaker became reduced to a system, the four smaller sizes than lump coal were soon graded. They were known as steamboat, egg, stove, and chestnut. It was thought at the time that no finer grade of coal than chestnut could be burned to advantage. But it was not long before a smaller size, known as pea coal, was separated, placed on the market, and readily sold; and now, within recent years, another still smaller size called buckwheat has been saved from the refuse and has come into general use. Everything smaller than this is culm and goes to the waste pile. The names of the different sizes of marketable coal and the spaces over and through which they pass in the process of separation are given in the following table, taken from Saward’s “Coal Trade Annual,” for 1888:—

Over.
Inches.		Through.
Inches.
Lump coalbars4½ to 9
Steamboat“3½ to 57
Brokenmesh2⅜ to 2⅞3¼ to 4½
Egg“1¾ to 2¼2⅜ to 2⅞
Large stove“1¼ to 1⅞1¾ to 2¼
Small stove“1 to 1¼1¼ to 1½
Chestnut“ ⅝ to ¾1 to 1¼
Pea“ ⅜ to ⅝ ⅝ to ⅞
Buckwheat“ ³∕₁₆ to ⅜ ⅜ to ⅝
Dirt“ ³∕₁₆ to ⅜