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It has a large flat blade with a straight edge. At the back is a peen or hammer head, and in the middle is a socket for the handle or helve, the blade and helve being in one line.

Lather's Hatchet

It has a large flat blade with a straight edge. At the back is a peen or hammer head, and in the middle…

Such a hammer will deliver a blow at every stroke of the piston-rod, and with sufficient air-pressure will give from 200 to 1,000 blows a minute

Pneumatic Hammer

Such a hammer will deliver a blow at every stroke of the piston-rod, and with sufficient air-pressure…