Although this is part of another post I made, I thought it was interestingly and important enough for this bit of the post to have a thread of it's own. I came across this odd referance today, in a puzzle book of all places.
http://flickr.com/photos/oldcatalogs/sets/72157604432587188/ (the whole book)
The specific page is on: http://flickr.com/photos/oldcatalogs/2397865946/sizes/o/in/photostream/
So even in a puzzle book from 1914, lockpicking & safcracking was considered a puzzle suitable for a hobby book, not criminal knowledge.
Does anyone else know of any other referances in old books to locks or safes being considered fun puzzles to "solve"?