Fantastic.

There only seems to be one copy of it still left - in a library in England. However there are photocopies and a reprint from Syd Waterman syd@lockcollectors.com

Hi,I have several YALE locks,look the same as yours,they are about 80 years old,The older ones had a swing cover on the bottom,chains are attached in different places on body of lock,I don't know...

I would prefer the way the Italian job did it. A shaped charge thou. Once the floor is gone the safe would drop. The only reason to use the lance is very little vibration.

After thinking that problem through a little more, making angled cuts would not only solve the likelyhood of binding, it would also move the cutter further away from the dropping floor slab and safe....