The folks at Tools for Working Wood
are painstaking scanning, retouching and making available (free) issues of a 120-year old magazine called, "Work: The Illustrated Weekly Journal for Mechanics
". If you're interested in woodworking, printing or old tools you'll love these, but Vol. 1, No. 13
has a set of plans on the cover for making a 'cheap enlarging camera'.
Thought all y'all might like to see it.