1843.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



11 





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Fig. 1.— View of the Old Tilting Hammer, 



Fig. 2.— Nasmyth's Direct Action Steam Hammer. 



as to cost, in some cases, nearly as much as the whole metallic part of 

 the apparatus. 



With respect to the action of such a forge hammer, as seen in 

 Fig. 1, it will be found that one grand defect in principle exists, 

 namely, that when engaged in hammering a large piece of work, as 

 that seen in the sketch, by reason of the work occupying the greater 

 part of the clear space between the anvil face and that of the ham- 

 mer, we have thereby a slight blow when we are doing a large piece 

 of work, and a heavy blow when we are hammering a small or thinner 

 piece of work, which is just the very reverse of what we could de- 

 sire. And in the execution of large work this is found to be a most 

 serious evil, in as much as, from the nature of the case, we would wish 

 to have the most powerful and energetic blows that it is possible to 

 command. The result of this is, that neither is the mass rendered so 

 sound as we could desire, nor is it brought to its required form except 

 by repeated heatings, at the very great sacrifice of time and iron, in 

 so far as, ere the limited blows of the hammer have produced the re- 

 quired change of form, the welding heat has gone off, and all blows 

 after this tend rather to loosen than compact or solidify the mass. 

 Again, we have, another very serious evil, namely, the very confined 

 limits of the space between the hammer face at its highest, and that 



Fig. 5.— Self-acting. 



of the face of the anvil, which renders it quite incapable of admitting 

 or operating upon a mass of any great breadth or height; and besides 

 having the machinery of the hammer quite in the way, in many 

 cases we have also this other disadvantage, namely, that except for 

 one thickness of work, the hammer face and anvil are not parallel, as 

 will be evident on referring to the sketch, and considering that the 

 face of -the hammer acts radial to the centre, S, Fig. 1, in which it 

 rocks. This evil is to a small extent obviated, by means being given 

 to raise up the tail or centre, S, but this process is not only difficult, 

 but can only be done between the heats. 



With a view to relieve all these defects, I have contrived my direct 

 action steam hammer, which is represented in one of its many forms 

 and applications in Fig. 2. 



It consists simply of a cylinder C turned as it were upside down; 

 that is, its piston rod comes out at the bottom of the cylinder instead 

 of (as in most cases) out of the top ; this cylinder is supported over 

 the anvil K by two upright standards, O, the end of the piston rod 

 being attached to a block or mass of cast irou, 13, guided in its descent 

 by planed guides or ribs cast on the edge of each standard. This 

 block of cast iron is the hammer or blow-giving part of the apparatus, 

 while the cylinder, with its piston and piston rod, supplies in the most 



