Not the LENGTH of the crank arm, but yes, the distance of the pedal shaft from the BB is adjustable. This was a common feature on the old bikes.

And yes! East Hill, I will take a camara on the next trip. I tried to borrow my daughter's this morning, but she claimed she needed it at school. I now know she wanted for after school at her girl friend's house--- for posting pictures on Face Book, most likely!