This site has two motors: one from 1938 and the other from a boy scout
manual. They both look like stuff I built in the '50s.
I also have my copy of the "Boy Mechanic" published in 1952 by Popular
Mechanics that has "5 Toy Motors" in it: a tin and nail, a synchronus,
an induction, series and mercury (yikes). If anyone is interested I
will gladly scan the book and foreward the section to you.

Richard