The tools used by the miner in the process of coal getting are comparatively few in number and of a simple character.

After the coal has been broken out it must be carried to the surface by some means or other. This demands the use of certain mechanical appliances which indirectly become part of the equipment of the miner. Thus the tools and equipment necessary to work the coal and raise it to the surface may be classified as follows

(1) Tools used in the act of coal getting, driving through barren ground, and blasting.

(2) Tubs and track for the roadways, self-acting inclines ; and all forms of mechanical haulage.

(3) Winding appliances for raising the coal from the bottom of the shaft to the surface.

(4) Pumping appliances for removing water from the mine to allow of the other operations being carried on.

In the operation of coal getting, picks are used for undercutting or holing, the coal being afterwards detached by wedges or by blasting. The coal is then ready for filling into the tubs. Thus the complete equipment of the working miner consists of a few picks, a wedge or two, a hammer and a shovel, with a boring machine and the necessary drills and tools for charging and tamping the shot hole when the coal has to be blasted.

Picks. — The miner's pick consists of a cast steel, or tool steel head or blade, about 18 inches long and from 1 to 1½ inches wide at the eye, and is fitted with a shaft of hickory or ash wood from 30 to 40 inches long. The blades weigh from 1½ to 3 pounds, the lighter for deep undercutting, the heavier for taking down and breaking up coal. For heavy stone work, picks up to 7 pounds weight are used. Common forms as made by the Hardy Patent Pick Co. are shown in Figs. 68 and 69. The 'Universal,' shown in Fig. 68, has a strong metal ferrule enclosing the upper part of the shaft. The blade is slipped over the end of the shaft and fits on to the tapered ferrule at the top. By this means the blade is easily attached or detached at will. In the case of the 'Acme,' shown in Fig. 69, the shaft is fixed in a socket, the blade being inserted in this socket, and held in position by means of a key. The chief advantage of detachable blades is that after use only the blades need be conveyed to the surface when resharpening is necessary. In the ordinary course of coal getting a collier may use two or three blades each shift. The number depends on the hardness of the material against which the pick is used, and also the quality of the temper that has been given to the steel by the blacksmith when sharpening them.

Wedges. — Steel wedges of different shapes, as shown in Fig. 70, and weighing from 2 to 5 pounds, are used for bringing down the coal. They may be used either before or after blasting, this depending on whether the coal is easily broken out or otherwise. The thin end of the wedge is placed in a notch made by a pick. It is then driven forward by means of a hammer, thus loosening the coal and forcing it away from the seam.

Hammers. — These are frequently called malls or mashes by the miner, and weigh from 4 to 8 pounds. They are usually about 2 inches across the faces or panes, and about 8 inches long, being fitted with an ashwood shaft about 30 inches in length. They are used for driving wedges, setting up timber, breaking coal, or any other work of a similar character. (See Fig. 71.)

Shovels. — Various forms of shovels are used, but as a rule the square-mouthed type shown in Fig. 72 is generally preferred by the collier. The shovel is made from a thin, steel plate, which is pressed into shape and fitted with an ash handle. The size of shovel and length of handle vary with the conditions of the working, small sizes with short handles being used in thin seams where the working space is confined, while larger sizes with longer handles are used in places where the working space is ample.

Boring Machine. — This machine consists of a screwed barrel fitted with a screw, the end of which is formed into a holder to carry the drill. Fixed to the screw, close behind the tool-holder, is a ratchet wheel, which is worked by means of a ratchet and pawl, carried on the operating handle. In using the machine a prop is firmly set against the roof at a suitable distance back. The machine with the short drill inserted in the holder is set up with the drill resting against the position where it is desired to bore the hole, and the barrel of the machine adjusted tight against the prop. The drill is then advanced by means of the screw, which is turned by the handle through the medium of the ratchet. When the screw has been advanced its full length, the machine is removed and the screw run back into the barrel. A longer drill is then inserted, the machine replaced, and the operation continued as before. A machine of the ordinary ratchet type is shown in Fig. 73.

For heavy stone work and long cross-measures drifts power-operated drills of either the percussive or rotary type are frequently used.

Scraper or Cleaner. — This tool, which is used for cleaning out the hole during the separate stages of boring, and finally before inserting the explosive, consists of a long rod of copper with a circular disc of about an inch diameter formed at right angles to the rod at each end. It may also be used for pushing back the explosive when charging the hole, and hence the reason why copper must be the material used.

Pricker. — This is a copper rod about inch diameter and 3 feet 6 inches long. It is fitted with an eye at one end and gradually tapers from that end to the point. It is placed in the hole after the explosive has been inserted, with its point penetrating the explosive. The hole is then stemmed up, after which the pricker is withdrawn, leaving a passage into which a straw filled with gunpowder or a squib is inserted for the purpose of firing the explosive. This method of firing is only permitted in mines where no inflammable gas or coal dust is found. The method, although handy and cheap, is dangerous, and firing by safety fuse or magneto-electrical apparatus is much safer.

Stemmer. — This is made of wood or copper, and is simply a rod with a slightly enlarged end in which a groove has been cut. After the charge has been placed in the hole, pieces of clay are rammed hard in on the top of it by the stemmer. The fuse, or pricker, if it be used, lies along the groove and is thus protected from damage while the stemming is being rammed home. In stemming a hole coal dust or coal borings must not be used, but clay or some other noninflammable material. The three foregoing tools are shown in Fig. 74.

Explosives and Blasting. — An explosive is a compound or mixture that has the property of being rapidly converted into gas upon ignition or detonation. When acting in a confined space the gases liberated at the moment of explosion exert a great pressure because they are not free to expand as rapidly as they would do if unconfined. This pressure exerted all round the seat of the charge tends to smash and break down the material in which the charge is placed.

Mining explosives are generally divided into two main classes

(1) Low Explosives, or those which are ignited by a flame, and (2) High Explosives which are discharged by shock or detonated.

Gunpowder, which is formed from a mixture of 73 parts of sodium nitrate (NaNO3), 16 parts of wood charcoal, and 11 parts of sulphur, belongs to the first class. Owing to the large amount of flame produced by this explosive its use is not permitted unless the mine in which it has to be used is free from coal dust and firedamp. There are other explosives of this class which contain certain ingredients intended to keep down the temperature and suppress flame at the moment of explosion, but their employment is restricted to blasting in coal, and then only allowed where the seam is of such a character that their use is not likely to cause danger. From the point of view of coal getting, explosives belonging to Class I. give the best results, as they are slow in action and rend the coal without smashing it into small. On the other hand they are more liable to ignite while being handled in naked light mines, and are a source of grave danger should coal dust or firedamp be present where they are used. For these reasons the Coal Mines Act places restrictions on their use.

High explosives as a rule contain nitro-glycerine as one of their chief constituents, but some types are made from ammonium or potassium nitrate with certain hydrocarbons, such as benzine, napthalene, and toluol. All high explosives require to be fired by means of a detonator. This detonator consists of a small copper tube about an inch long and one quarter inch diameter. It is charged with dry fulminate of mercury or a mixture, of fulminate of mercury and potassium chlorate, the charge filling the copper tube about one-third of the way up. A detonator must contain sufficient fulminate of mercury to produce an initial shock capable of decomposing the explosive with which it is used. As all high explosives do not detonate with the same degree of shock, detonators containing different weights of detonating compound are manufactured to suit the various classes of explosive with which they are to be used. Detonators are numbered from No. 1 to No. 8, and contain from 4½ grains of fulminate of mercury in No. 1 to 30.9 grains in No. 8. The greatest objection to the use of high explosives for coal-getting is that their action is local and tends to shatter the coal.

Explosives of the Ammonium Nitrate type produce few inflammable products, give off comparatively little heat at the moment of explosion, and require strong detonators to set them off.

Only those explosives that have passed a severe Government test are allowed to be used in fiery or dusty mines, and only when all traces of firedamp have been removed from the vicinity of the shot, and all dust within a given distance has been rendered harmless by watering.