Thursday, 24th July 2008 by James Turnbull
The Phoenix Shot Tower in Baltimore was erected in 1828 and stands at 71.3m, which at that time made it the tallest structure in the United States, as well as the world’s largest free-standing masonry tower1.
The shot tower was invented by an Englishman in 1783, and soon spread across the globe as the preferred method of making lead shot for shotguns.
The process involves pouring molten lead through a copper sieve at the top of the tower, so that droplets fall the height of the tower, taking the form of tiny perfect balls during their descent. The lead then splash-lands in a water bath at the bottom, which sets the pellet.
These days shot is made using a centrifuge, so now only a handful of the once-ubiquitous shot towers exist worldwide.
The largest shot tower that was ever built is the 80.16m tall Clifton Hill Shot Tower in Melbourne.
Probably very impressive in 1882 when it was completed, but by the standards of today’s tallest towers, it’s tiny!
More info on shot towers at Wikipedia.