A common highlight of 4th of July festivities in the early 1900s was the firing of anvils. Two anvils are used, one for a base and the other place on top. The base anvil has a small cavity where black powder is placed with a fuse. Depending on the kind of charge, depends how high the top anvil will shoot up. More importantly, is for the the fired anvil to come crashing down on the base anvil creating a spectacular sound. You can see examples of this on You Tube.