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20 also the Canadian or American pattern shown by Fig. 95. The adze has a long, curved handle, and the operator stands with one foot upon the wood in the line of the fibre, and thus assists in steadying the work. The variety in the shape of the adze heads is very great, but it is sufficient here to show the Scotch pattern (Fig. 96).

Screwdrivers.—These are tools of impulsion, and at least two or three will be required—long and short, and with wide and narrow blade. For general work, a tool of medium length should be obtained, although there are, on the one hand, enthusiastic advocates of a short tool, and on the other hand of a long tool for each and every purpose. Any advantage gained by a short over a long tool, or the reverse, is one of advantage in special circumstances only, and not one of saved energy; theoretically,

Fig. 96.—Scotch Adze Head.

the length does not enter into consideration at all, except when, in starting to extract a difficult screw, the driver is tilted from the upright; but this is at the risk of a broken tool edge and defaced screw-head. The worker then must decide for himself as to which sizes will best suit his purposes. London screwdrivers have a plain handle (Fig. 97) or oval handle; cabinet screwdrivers are lighter tools, and there is, indeed, a great variety of patterns from which the worker can choose the tools that suit him. The gimlet-handle screwdriver has certain proved advantages; and the brace screwdriver—a screwdriver bit used in an ordinary brace—is useful for driving good-sized screws easily and quickly. Short screwdrivers are used in screwing on drawer locks, there being a much heavier though just as short a tool used for screwing up plane irons. Automatic screwdrivers (Fig. 98) were introduced from America, and by their means the screw is driven home merely by pressure on the top of the handle.

Bradawls.—These have round stems and chisel edges (Fig. 99); thus the edge cuts the fibres of the wood and the wedge-like form of the tool pushes them aside. Its special use is for making comparatively

small holes in soft wood, and the principal limitation of the tool is that there is no provision for the waste material.

Gimlets.—These are made in many forms, the best known being the twist (Fig. 100) and the shell (Fig. 101), lesser known shapes being the twist-nose (Fig. 102) and the auger (Fig. 103). Gimlets will bore end grain as well as across the fibres, but there is a risk, in boring a narrow strip, of the pointed screw splitting the wood.