What a great historical piece you have there Doug.
As it does not have permenant magnets and the crank is not geared the output as a generator will be tiny.
It was probably used with a galvanometer wired to show output as well as direction change.
I wish I had an early galvanometer! It did actually read about .2 volts on my meter, so maybe it is working, just not what I was expecting. Thanks,
Doug
There are some on ebay both old and new.