“Liberty Bell,” Wikipedia.
“The Liberty Bell,” this blog, 4/16/2017.
Our own Fred Weinstein sent me photos he took on a trip to London in 2009 where the firm Whitechapel Bell Foundry claimed to be the manufacturer of the Liberty Bell. They had been in business since 1570, so Fred reasoned they were hardly inexperienced in casting bells, as I had suggested.
Maybe so. Casting bells was always a chancy art with uncertain results. That part of the story is also interesting.
In 1751, Philadelphia civic authorities commissioned the casting of a “good bell of about 2,000 pounds weight” from Whitechapel for the Pennsylvania State House (later renamed “Independence Hall”). Back then, Whitechapel Bell Foundry was simply named “Lester and Pack” (sounds like a vaudeville comedy team).
The bell arrived in Philadelphia in August, 1752, but the bell tower was not yet finished, so they hung the bell from a stand to try it out. At the first strike of the clapper, the rim cracked. The company of Lester and Pack blamed the bell ringer who allowed the clapper to strike the rim rather than the body of the bell. The Philadelphia authorities tried to return it, but the ship captain who brought it could not fit it back on his ship.
It looked like Philadelphia was stuck with a one-ton broken bell.
Two local founders (metal casters), John Pass and John Stow, offered to recast the bell, although they had no experience with bells. Pass headed the Mount Holly Iron Foundry, and Stow was only four years out of his apprenticeship as a brass founder (bells are of bronze). The English bell was broken into small pieces and melted down in Stow’s foundry on Philadelphia’s Second Street, where it was recast.
Pass and Stow thought the English metal was too brittle, so they added 10% copper. The finished bell did not crack, but that was the one said to sound like two coal scuttles banged together. Pass and Stow were embarrassed by the very public results and recast it again, using a further adjusted alloy.
That second recasting had acceptable sound, although not to everyone’s liking. That was the bell that eventually became the Liberty Bell.
(The bronze alloy of copper and tin used in a bell is a difficult compromise between being hard enough to produce a good tone, but not so hard that it will be brittle. Increasing the tin content hardens the bronze. Back then, bell casting involved much trial-and-error.)
The modern study by Winterthur Museum in 1975 suggested that Whitechapel initially erred in creating an alloy with too much tin. Pass and Stow’s addition of copper was the correct approach, but they added too much. They compounded the error on their second casting by adding cheap pewter scrap to the mix as a source of more tin. Pewter in those days, especially cheap pewter, also contained lead. Plus the alloy was inconsistent because they failed to sufficiently stir the melt. Not only did this produce a brittle bell that eventually cracked, it allowed later souvenir hunters to chip pieces from the rim.
If Pass and Stow had any idea the bell would become so important, they would have been more precise. I suspect their attitude was to try anything since they were working with scrap and there was nothing to lose. With this series of mistakes, no wonder many recommended throwing it all out and starting fresh.
If I were an official of Whitechapel today, I would not mention the Liberty Bell, especially not to our Fred, a Philadelphia resident.