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Page:Popular Science Monthly Volume 38.djvu/182

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170
THE POPULAR SCIENCE MONTHLY.

The "hammer" was undoubtedly the first tool invented by man, and it is still not only the simplest but positively the most important tool in use; without its pioneering blows other tools could not have been fashioned, and the materials of which they are composed would have lain dormant in the earth's crust forever; for the ringing of anvils under the beating of hammers was the absolutely essential overture to the grand opera of the civilization of the human race.

If it was intended that the metal be drawn out on an anvil by "hand-hammers" and "sledges," the soft mass of iron, as it was taken from the "blomary-fire" or other furnace in which it was reduced from the ore, was cut by means of a hatchet (as shown at M N, Fig. 13) into parts not too cumbrous to be handled by ordinary smiths' tools; these pieces were then heated in a fire of larger size, blown by more powerful bellows than were commonly used by a blacksmith. One of these enlarged smiths' fires is shown in Fig. 15 (taken from Swedenborg's De Ferro), and the tools used are shown scattered about the floor. It will be noted that there are two bellows, and that these are operated by a water-wheel.

When, as was usually the case, the purpose was to make from the iron bars and rods for the general purposes of trade, the bloom resulting from shingling (as before described) the spongy mass of crude iron was reheated and drawn into the desired shape under the blows of a ponderous piece of machinery called a trip-hammer. This, although of the same name, was quite different in construction from that already described as having been used for shingling the crude iron. One of these forge triphammers is shown in Fig. 16, in which H is the head of the hammer; this was sometimes made of wrought iron, but more often was cast of the proper form and provided with an aperture through which the wooden beam forming the "helve" was passed and secured by wedges. W is the anvil, and a the "bloom," whose movements are guided and controlled by the "hammer-man" (3); while his assistant (2) determines the rapidity and force of the blows, by varying the amount of water supplied to the waterwheel which actuates the hammer. The clumsy, heavily iron-hooped, wooden shaft Y, of the water-wheel, was in this instance placed parallel with the helve of the hammer. Fastened in the circumference of this shaft were a number of round wooden pins, which, as they successively came in contact with the under side of the helve, forcibly threw it up against the spring-beam, 13, whose recoil increased the velocity of descent of the hammer and consequently the force of the blow.

Unless the bars made were of very great thickness, only a part of the bloom could be drawn out before it became too cold