Assertion: hammer's part | /r/HasProperty | compressed under hammer
Facets:
Source sentences:
text: The piece travels through the rolls very rapidly, so that the reduction takes place over its whole length in a very few seconds, whereas in forging, whether under hammer or press, after one part of the piece has been compressed the piece must next be raised, moved forward, and placed so that the hammer or press may compress the next part of its length.