What is "power hammer"

n. a power tool for drilling rocks [syn: hammer]

Power hammers are mechanical forging hammers that use a non-muscular power source to raise the hammer preparatory to striking, and accelerate it onto the work being hammered. Also called "Open Die Power Forging Hammers." They have been used by blacksmiths, bladesmiths, metalworkers, and manufacturers since the late 1880s, having replaced trip hammers.