I thoroughly enjoyed your search for the working model of the SPRAGUE, and the happy ending. I am the great-great niece of Captain Peter Sprague. I am from the Pittsburgh area and when I was young we visited the SPRAGUE model at the Carnegie Museum. It was situated in a dark corner. My father, George Sprague, asked the security guard to show us the "working" model. He then placed a key in the wall to turn it on. The paddle turned and the lights came on. Years later I learned it had been removed from the display and I assumed it was in the basement of the museum. Thank you for your 18 year search!