This is a great research book for early electric motor collectors. "How to Build a One-Fourth Horse Power Motor or Dynamo" by A.E. Watson, illustrated with 16 working Drawings (2 and 3 view shop floor drafting prints), Bubier Publishing, Lynn Mass © 1894. This is a small cloth and card bound book with a great deal of "how to" detail. If you ever wanted to construct a bi-polar motor, or if you just want to understand how they work, this is perhaps the perfect down to earth book for you, written in good old "Working Man's" English.