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Sledges are often made at the mines where they are used. The head then consists of wrought-iron with steel panes. The eye is generally punched hot, out of a short square bar of iron of suitable size, and a drift is worked in to keep the eye in shape while the sledge is being forged.

Bar-iron being generally manufactured by rolling, at a welding heat, a pile of separate pieces of iron, has often a laminated or leafy structure, due to imperfect welding in its manufacture, which can be detected on inspection. Fig. 40 shows this laminated feature as it would appear in the section of a bar.

When sledges have to be made out of such a bar, the eye is not as strong if punched with the laminæ, according to Fig. 41, as if punched across, as in Fig. 42. If sledges are to stand well, it is important to punch the eye across the lamina; but many smiths overlook this point, and sledges punched the other way are constantly splitting in use. Bully-heads are often forged as follows:

A bar of iron, say 2 inches square and 13 inches long, is cut off. This will make two 81b. sledges. One set of corners is chamfered down in the cutting-off heat, as shown by Fig. 43. The eye, a, is next punched, and then b, and the sledges

are divided by a clift, one set of corners being chamfered down, as shown by dotted lines, all in the same heat which was drawn for punching b. Afterwards the other sets of corners are similarly chamfered down by new heats, and both sledges are ready for "steeling." For this purpose is used a flat bar of good blister or shear steel of about 2 inches wide by inch thick. One end is heated to redness, and after about 2 inches have been nearly severed with a clift, as in Fig. 44, it is bent, and two corners hammered down on the anvil, as in Fig. 45. Then, by bending it the opposite way, the two other corners are hammered down similarly, as in Fig. 46, where it an eight-square outline, and forms a pane for the sledge, attached to the bar by only a slender neck. The steel pane is next welded on. This is done by heating the steel and one end of the sledge separately. When a welding heat is drawn-sand having been used to form a glazethe sledge is rapidly placed on the anvil, with the heated end uppermost, and the hot steel pane being quickly laid on, with the sides corresponding with the iron part, as in Fig. 47, a few light hammer blows on the surface of the steel pane weld it firmly to the iron, and by twisting the steel bar it breaks off at the narrow neck, leaving the pane properly attached.

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The chamfers are then dressed with a hammer, and after the opposite face has been treated similarly, the sledge is hardened by heating both faces to redness, and plunging it into cold water until quite chilled, upon which it is finished. Although the faces are not tempered at all, they are often found to be too soft, and this arises from the violent ebullition which the hot sledge produces when immersed, and which prevents the water from coming into close contact with the steel, so that it is cooled too slowly to be sufficiently hard. If streams of cold water are made to play with some force against the hot panes, they are always found to be well hardened.

When these sledges are made well, out of good iron, they stand a great deal of wear, and possess the advantage of being easily re-steeled when the panes are worn out. If, however, they are defective in quality, or workmanship, they are very liable to break by splitting, or giving way across the eye. A smith and two strikers will commonly forge eight 71b. bully sledges per day, and turn them out of hand in a workmanlike manner. This is a fair day's work, although some smiths, after getting well used to the work, can do ten. The cost may be arrived at as

follows:

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3.60 pence per lb., or nearly 32d.

The cost of coal, wear and tear of tools, &c., would amount to a trifle, say d. to 1d. per lb., extra.

Similar sledges can be bought ready-made by the cwt. at about the same rate; but they do not, as a rule, stand as much work as home-made sledges, and it is sometimes necessary to make sledges at the mine in order to fill up the smith's time. A smith and striker can re-steel about twelve of these sledges (twenty-four panes) per day. Excellent solid cast-steel sledges are now procurable from steel manufacturers at 9d. per lb. for sizes above 6lbs. weight, and increasing to 1s. per lb. for smaller sizes. Occasionally these sledges break by cracking, after which they cannot be repaired; but if they are well made, and used carefully, they are remarkably durable, and are becoming very favourite amongst some miners, many of whom claim that they give a "smarter" and more effective blow than steeled iron sledges.

PICKS.

THE pick is notably a miner's implement. In different districts it is called either a "mandrel," "pike," "slitter," "mattock," or "hack."*

Fig. 48 shows the common pick. The head is usually made of wrought-iron with steel at the

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tips," a, a, b, b, which form the wearing parts. An eye is formed at e, to receive the handle or "helve," which is secured by a wedge (shaded dark), and the sides of the eye are spread out to form "cheeks," as at f. About half of the head, viz., f, a, or f, b, is occasionally termed a "shank," or "stem." The "helve" is ordinarily made of ash ; and the part g, formed to suit the eye, is called the "feather," while h is called the "haft," which is made of a suitable size for holding in the hands, and is usually oval in shape. There are many other patterns of picks to be noticed presently. The action of a pick is very similar to that of a sledge, but the tools are of different utility. While

*This tool is said to be represented on Egyptian monuments of great antiquity.

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