Coal scuttle

“ So, too, the enormous hills of anthracite-coal dirt, that in the coal regions of our State have for years borne silent but eloquent testimony to the crudity and wastefulness of our methods of mining coal, now bid fair soon to disappear beneath boilers supplied with ingenious dust-burning devices, or in the form of lumps of artificial fuel. ”

“ At the beginning of the present century the anthracite or stone coal was in general use, in all the districts where it was found, as a fuel for the blacksmith’s fire and the iron worker’s forge. This, however, was the limit of its utility. It was thought to be necessary to force a strong artificial air current up through it to make it burn, and since this could not well be done in grates, stoves, or furnaces, there was no demand for coal for domestic use, or for the great manufacturing industries. ”

“ This fact explains, also, why in mines of wood-coal carbonic acid, i.e. choke-damp, alone is given off. For in the wood-coal a great deal of the hydrogen still remains. In mines of true coal, not only is choke-damp given off, but that more terrible pest of the miners, fire-damp, or explosive carburetted hydrogen and olefiant gases. Now the occurrence of that fire-damp in mines proves that changes are still going on in the coal: that it is getting rid of its hydrogen, and so progressing toward the state of anthracite or culm—stone-coal as it is sometimes called. ”

“ As far as the gas-making properties of the first three are concerned, the relative proportions of carbon and volatile products are much the same. Everybody knows a piece of cannel coal when it is seen, how it appears almost to have been once in a molten condition, and how it breaks with a conchoidal fracture, as opposed to the cleavage of bituminous coal into thin layers; and, most apparent and most noticeable of all, how it does not soil the hands after the manner of ordinary coal. ”

“ Thus the freedom of burning increases with the amount of volatile hydrocarbons, while the heating power depends on the amount of fixed carbon present. Sulphur is an injurious constituent when the coal is to be used in the manufacture of gas or for metallurgical purposes; while ash is undesirable, since it displaces so much carbon, and if it contains fusible impurities such as iron, lime, or alkalies, it causes clinkering. Moisture retards the heating power of the coal until it is driven off. ”

“ The soft coals, on the contrary, being porous as well as soft, allow the gases to escape from them much more readily, and so increase the danger at the working faces of the mines. The gas given out most abundantly by the coal is light carbureted hydrogen, known as marsh gas, from the fact that being a product of vegetable decomposition under water, bubbles of it rise to the surface on stirring the waters of a marsh. This is the gas that is known to miners as fire damp. ”

“ It is estimated that sixteen per cent. of the material which goes into the breaker to be prepared comes out as waste, and is sent to the refuse dump. It can readily be supposed, therefore, that in the course of a few years these waste heaps will grow to an enormous size; and as a matter of fact they do. The dirt or culm, which includes all material [190] finer than buckwheat coal, is usually dumped on a separate pile from the rock, slate, and bony coal, since it is not wholly without at least prospective value. ”

“ On the north side only, however, has it been followed under the basalt, and that for but a very slight distance; and in every instance in which this has been attempted the coal has been found to be "blacked" and to be fractured, and frequently to pass into "rock and rig." A coal is said in this district to be "blacked" when, by its near proximity to an igneous rock, it has become so altered as to lose all its brightness, and nearly, if not quite, all its inflammability. ”

“ It is not thought to be given off in appreciable quantities by the coal at the open faces; but it is formed when the carbonic acid passes through any ignited carbonaceous material, or when steam passes over burning coal. It is therefore produced most frequently by smouldering gob fires, by burning wood in the mines, or by a shaft on fire, and may exist as one of the results of an explosion of fire damp or of blasting powder. It is the most to be dreaded of any of the gases which the miner has to encounter. ”

“ Mining coal is dangerous work. Any blow of the pickaxe may break into a vein of water which will burst out and flood the mine. The wooden props which support the roof may break, or the pillars of coal may not be large enough; and the roof may fall in and crush the workers. There are always poisonous gases. The coal, as has been said before, was made under water, and therefore the gas which was formed in the decaying leaves and wood could not escape. It is always bubbling out from the coal, and at any moment a pickaxe may break into a hole that is full of it. ”

“ The boy who sits below him on the shute is able to give the passing stream a closer inspection and more careful treatment, and, should there be one still below, he must have sharp eyes and skillful fingers to detect worthless pieces that have been left by his comrades. The boys often put their feet in the shute and dam the coal back for a [187] moment to give them time to throw out the abundance of slate that they may see, but no matter how careful they are, nor how many hands the coal may pass through in the picking process, a certain percentage of slate and bone is sure to remain. ”

“ To the poor people who live in the vicinity of the breakers these heaps of refuse coal are an unmixed blessing. Pieces of good coal are always being thrown out inadvertently with the waste, and the bony coal that is discarded is not by any means without value as a fuel; indeed it makes a very respectable fire. So, too, one can obtain, with a screen, from the culm heap quite a little percentage of material that will burn. ”

“ The presence of more than 1% of sulphur renders coal unfit for the economical production of good light-gas, and more than 2% of sulphur renders it objectionable for use as domestic fuel. In like manner, coals containing mineral ingredients in excess are to be avoided, not merely on account of the quantity of ashes left by them, but for their tendency to vitrify upon the bars of the furnace, and to produce what is technically called ‘clinkers.’ The presence of much silica or alumina, and more particularly of any of the salts of lime, in ‘steam coal,’ is, on this account, highly objectionable. ”

“ This causes a cloud of black dirt, and the front of your house suffers. Then coal must be shovelled up into scuttles; often it is necessary to break up the large lumps. The scuttles are then carried about the house, coals up, ashes down; grates are cleaned and the room is powdered with dust in the process. Grates, fenders, fireirons, and coal-boxes must be cleaned, and fashion ordains that they are generally made, wholly or partly, of polished metal. The weather is cold and a servant is rung for and more coal is demanded. One day the wind blows and the fire will not light. ”

“ What is called caking coal yields about 40 per cent.; when burning it swells, agglutinates, and emits much smoke and gas, which inflame at a certain temperature. Cannel coal has only 20 per cent. of bitumen, and does not agglutinate or cake. It burns with a bright flame like a candle, from which circumstance it takes its name, cannel being the common pronunciation of candle in the North of England. The third sort I shall mention is called anthracite by mineralogists; but its common name is blind coal, or Kilkenny coal, from a district in Ireland, where there are vast beds of it. ”

“ The first cause is probably the most important, and this is particularly true of anthracite coals where a sliding scale of prices is used according to the season of the year. While market conditions serve as one of the principal reasons for coal storage, most power plants and manufacturing plants feel compelled to protect their coal supply from the danger of strikes, car shortages and the like, and it is customary for large power plants, railroads and coal companies themselves, to store bituminous coal. ”

“ The sulphureous vitriolic steams that issue from the pyrites, which frequently, if not always, accompanies pit coal, ascending with the flame, and poysoning the ore sufficiently to make it render much worse iron, than that made with char coal, though not perhaps so much worse, as the body of coal it-self would possibly doe. ”

“ But accidents due to a flooding by surface water are not always to be obviated. Sometimes when a stream crosses the line of outcrop the water will break through into the mine and flood the lower levels in an incredibly short space of time; and this too when good judgment and prudence have been used in leaving sufficient coal for protection. The continuity and character of the strata lying between the earth’s surface and the coal face cannot always be determined. It is not often that accidents from flooding occur while mining is going on under large bodies of water. ”

“ On our knees we pushed the buggy into the room, took up the hammer, broke up the coal into lumps we could handle, filled up the small box, dragged it out into the entry and emptied it into a heap. This is called "buggying" coal. It is the most laborious part of mining. Whenever a new man would be placed with the convicts for instructions in mining he would have to buggy coal just as long as it was possible to get him to do so. ”

“ From this experiment, it appears, that 66.5 grains of cannel coal contain 50 grains of charcoal, and 2.08 of earth; the remaining 14.42 grains must be bitumen. In a similar manner, by knowing the quantity of coal required to decompose a given quantity of nitrate of potassa, when melted in a crucible, the quantity of carbon in any variety of this substance may be ascertained.
With respect to the earthy and metallic ingredients of coal, we may ascertain them by burning the coal, with free access of air. What remains unburnt must be considered an impurity. ”

“ But the driving of the stalls themselves is a work involving no little waste of coal and insecurity to the colliers; the mass of coal of eight yards wide having to be undercut, or holed about a couple of yards in, a large amount of coal is cut up into slack by the "pike," or collier's pick, and the men are exposed to continual risk from falls of coal. As the various portions of the seam are successively "cut" at the side of the stall, and brought down, the colliers have to mount on heaps of slack or light wooden stages, and are necessarily exposed to still greater danger. ”

“ It is their duty to pick out the pieces of slate, stone, or bone, from the stream of coal which passes under them, and throw this refuse into a trough at the side of the shute, from which point it slides rapidly away. The coal as it comes from the mine is full of waste material, so that the boy who sits first or highest on the shute has no trouble in finding plenty to do, and, work as hard as he may, much of the unfit material must still escape him. ”

“ The process of mining coal is a combination of boring and digging. Shafts are sunk, levels are driven, and drains are carried off, by the help of picks or pickaxes, wedges and hammers, the rocks being also sometimes loosened by blasting with gunpowder. In searching for coal, a shaft is sunk through the uppermost soft stratum, and the rock is then bored, by striking it continually with an iron borer terminating in an edge of steel, which is in the mean time turned partly round; and, at proper intervals, a scoop is let down to draw up the loose fragments. ”

“ When the oxidation has been sufficiently prolonged, anthracite or free-burning coal, as pure as possible, is thrown upon the surface of the metal, and after a short time the thick end of a long birch or oak pole is plunged into the molten mass. This part of the operation is termed ‘poling.’ The wood in contact with the copper is rapidly decomposed; much gas is evolved, which causes the metal to be splashed about, and every part of it to be exposed to the reducing action of the coal. ”

“ So it is that by hard work and much danger we get coal for burning. Now, coal is dirty and heavy. A coal fire is hard to kindle and hard to put out, and the ashes are decidedly disagreeable to handle. And after all, we do not really burn the coal itself, but only the gas from it which results from the union of carbon and oxygen. In some places natural gas, as it is called, which comes directly from some storehouse in the ground, is used in stoves and furnaces and fireplaces for both heating and cooking ”

“ In many of the surface exposures and in the tunnels, drifts and open cuts where development has been carried on, the coal is soft and friable. Even where fairly firm and unbroken masses of coal are found, they can be readily crushed. It is difficult to find large lumps of coal free from fractures and slickensided surfaces. During mining, such coal can not escape being badly broken, and the difficulties of shipping will be great. ”

“ Such facts merely imply that portions of the areas of coal accumulation were liable to inundation of a character so temporary as not finally to close the process, as happened when at last a roof shale was deposited by water over the coal. Cannel coals and bituminous shales holding mussel-like shells, fish scales, etc., imply the existence sometimes for long periods of ponds, lakes or lagoons in the coal swamps, but ordinary coal did not accumulate in these. ”

“ The partial use of pit coal in the process of smelting was revived in Coalbrookdale, in Shropshire, about 1713. The chief difficulty was to keep the coal in a state of combustion sufficiently intense for the purpose of smelting the ore; the hand-worked bellows, or the more powerful 350water movement, which produced blast enough for charcoal, having comparatively little effect upon coal. ”