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NEW Y O 11K:
3D. APPLET © N & COMPAN^
549 & 551 BROADWAY.
1874.

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Entered, according to Act of Congress, in the year 1851, by

D. APPLETON & CO.,

In the Clerk's Office of the District Court of the United States for the Southern

District of New York.

Entered, according to Act of Congress, in the year 1868, by

D. APPLETON & CO.,

In the Clerk's Office of the District Court of the United States for the Southern

District of New York.

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HACKLE Ok HAX. A kind of comb or brush made of iron spikes; used for combing or pulling the fibres of wool or flax, so as to reduce them from a tangled to a smooth state.

HADE. In mining, the underlay or inclination of the vein.

HALF-TIMBERED HOUSES. Buildings in which the foundations and principal supports were of itont timber, and the interstices of the fronts were filled with plaster.

HALLIARDS. In navigation, the ropes or tackles usually employed to hoist or lower any sail.

HAMMER. A well known carpenter's tool. Fig. 2243 represents a modification *?°^

known as Anderson's Patent Hammer. In this hammer, the claw, as will be seen by the cut, extends to the handle and clasps it with a strong ring, which makes it impossible, in drawing nails, for the handle to give way, draw out, or become loose. The face of the patent hammer will thus always remain true, it being kept at the same angle with the handle. Six different sizes are now made, weighing from half ll pound to one and a half pounds.

HAMMER, steam. James Nasmvth's patent steam-hammer. Before proceeding to describe the principle, mode of action, and constructive details of the direct-action steam-hammer, it may be proper to make a few remarks on the ordinary forge-hammers, so that the nature of the advantages possessed by the steam-hammer may be more clearly understood.

In all forge-hammers previously in use, the force necessary to set them into operation had to bo transmitted in a very indirect manner,—for whether a water-wheel or steam-engine were the moving power, the requisite lifting and falling action of the hammer had to be produced by the employment of rotatory motion, thus rendering necessary the use of wheels, shafts, cams, and other cumbrous details, which, together with the apparatus requisite to connect the various parts of the machinery, and give due strength and solidity to the whole, not only caused great outlay and sacrifice of valuable space, but also occasioned much loss of power, by reason of the very circuitous manner in which the force of the prime moving agent had to travel ere it reached its final destination, and came forth in blows from the forge-hammer. Great inconvenience, also, was found to result from having a considerable portion of the working machinery close to the hammer, as thereby a very serious impediment was offered to the free execution of; the work. And when we add to this very limited range in the clear fall of an ordinary forge-hammer, (seldom, in any case, exceeding 18 inches,) causing the force of the blow to decrease in a very rapid ratio, with a moderate increase in the diameter or depth of the work; and when we take into consideration the fact that, in consequence of the helve of the hammer working on a centre or joint, its face a parallel to that of the anvil only at one particular distance; and finally, when to this list of inconveniences we add that in the ordinary forge-hammer we possess no power or control over the force of its blows, but are compelled to make the best use we can of them, whether they be adapted to our purpose at the time or otherwise, we find inherent in the very principle of such hammers, a combination of evils and inconveniences that only excite surprise that they should have been suffered to exist for so great a length of time.

This remark is most strikingly applicable in Oiecaseof those forge-hammers which receive their power from a steam-engine, inasmuch as the power in question originates in the motion of the piston, m the very state and condition in which, for the purpose of hammering, we desire it ultimately to be, namely, as a straight up and down motion; so that instead of causing this reciprocating action of the piston-rod to pass through all the complex media of beam, connecting-rod, crank and cam shaft, for no

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