I have several old American books dated 1946 on rewinding motors, and in one it describes a 2 speed single phase motor with two sets of winding for each speed. No mention of a capacitor though. Should any one be interested in motors of all types. I can recommend "Electric Motor Repair" editor Robert Rosenburg and "Armature Winding and Motor Repair" by Daniel H Braymer ,there a few British ones as well but not so comprehensive. John