IRON 



1013 



..The hammers, fig. 1274, are made entirely of cast iron; they are nearly 10 feet 

 long, and consist usually of two parts, the helve c, and the head or pane d. The 

 latter enters with friction into the former, and is retained in its place by wedges of 

 iron or wood. The head consists of several faces or planes receding from each other, 

 for the purpose of giving different forms to the ball lumps. A ring of cast iron, a, 

 called the cam-ring bag, bearing moveable cams, b b, drives the hammer, d, by lifting 

 it up round its fulcrum, /, and then letting it fall alternately. In one iron work this 

 ring was found to be 3 feet in diameter, 18 inches thick, and to weigh 4 tons. The 

 weight of the helve (handle) of the corresponding hammer was 3 \ tons, and that of 

 the head of the hammcT 8 cwts., 



1274 



XIXIXIXIXTX 



The anvil, e, consists also of two parts ; the one called the pane of the anvil, is the 

 counterpart of the pane of the hammer ; it likewise weighs 8 cwts. The second, g, 

 named the stock of the anvil, weighs 4 tons. Its form is a parallelepiped, with the 

 edges rounded. The bloom or rough ball, from the puddle-furnace, is laid and turned 

 about upon it, by means of a rod of iron welded to each of them, called a porter. 

 Since the weight of these pieces is very great, and the shocks very considerable, the 

 utmost precautions should be taken in setting the hammer and its anvil upon a sub- 

 stantial mass of masonry, as shown in the figure, over which is laid a double, or even 

 quadruple, flooring of wood, formed of beams placed in transverse layers close to each 

 other. Such beams possess an elastic force, and thereby partially destroy the inju- 

 rious reaction of the shock. In some works a 6-feet cube of cast iron is placed as a 

 pedestal to the anvil. 



Forge-hammers are very frequently mounted as levers of the first kind, with the 

 centre of motion about one-third or one-fourth of the length of the helve from the cam- 

 wheel. The principle of this construction will be understood by inspection of fig. 1275. 

 The short end of the lever, 



which is struck down by the 1275 



tappet, 6, is driven against the 

 end of an elastic beam, t, and 

 immediately rebounds, causing 

 the long end to strike a harder 

 blow upon the anvil, *. 



Fig. 1275 is the German 

 forge-hammer; to the left of 

 1 is the axis of the rotatory 

 cam, 2, 3, consisting of eight 

 sides, each formed of a strong 



broad bar of cast iron, which /&Ss'' ^ 



are joined together to make the 

 octagon wheel. 4, 5, 6, are cast- 

 iron binding-rings or hoops 



made fast by wooden wedges ; 6, b, are standards of the frame-work, e, I, m, in which 

 the helve of the forge-hammer has its fulcrum near u ; h, the sole-part of the frame ; 



