Hi, I'm really hoping you can help me out. I'm an author doing research for a book about a ten year old girl who is an ace puzzle solver and lock-pick. I would like to make sure my information is accurate and so would appreciate help understanding what sorts of locks would have been most often used in that era.

The passage of time I'm really interested in is 1840-1910, and I'm mainly concerned with uk locks.

So can you help me find out what sorts of locks would have been used a lot? And what kind of lock-smith skills would have been most essential? I'd love your thoughts on:
- locks that would have been used on external doors
- padlocks for wagons, boxes
- safe locks
- internal locks: for instance, what sort of lock would be used to lock a classroom door?

If you can help me with any of this, or point me in the right direction I would be so grateful.

Thanks in advance!