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Electric motorIn 1904, the first direct current, interpole, electric motor to be patented in the U.S. was issued to Mathias Pfatischer of Phildadelphia, Pennsylvania under the title "Variable Speed Motor" (No.775,310). His improvement was to "effect commutation without sparking, with a variable load as well as at variable speed and which is capable of rotation in either direction." The new design added auxiliary-field pole-pieces which were small as compared to the main pole-pieces.«
Ponderings Collection 09
Why call then hot water heaters if the water is already hot?
If you throw a cat out a car window does it become kitty litter?
If corn oil comes from corn, where does baby oil come from?
If there is no God, who pops up the next Kleenex in the box?
When a cow laughs does milk come up its nose?
Why do they put braille on the number pads of drive-through bank machines?
How did a fool and his money GET together?
If nothing sticks to Teflon, how do they stick Teflon on the pan?
How do they get a deer to cross at that yellow road sign?
If it's tourist season, why can't we shoot them?