Use of pitch standards by foundries

[oakcroft13]

Michael Wilby asks when the foundries adopted pitch standards. Though 
I can't answer this question directly, I can give two pieces of 
evidence.

I understand that at Whitechapel it was common practice a hunderd 
years ago to tune bells by filing up a set of tuning forks to the 
flattest bell in the peal after casting and then tuning the bells to 
these forks.

I have seen at Taylors a set of books, copied out I think by Paul 
Taylor, giving the correct frequencies for equal tempered intervals 
based on a wide range of base frequencies separated by one or two Hz.

This suggests that in both cases they tuned bells as they found them 
rather than aiming for particular absolute frequencies.

Steve Ivin suggests that carillons might be tuned to some absolute 
pitch standard. I have not analysed enough carillons to make any 
meaningful comment, but note that most (modern) carillons are 
transposing instruments, where the nominal names given to the notes 
on the keyboard is usually different to the actual pitch of the bells.

Bill H