Pins on Brass

I peeled the slick greaseproof paper off the brass spindle right across the hearth stones. The brittle wrapper tore into amber flakes, sticking to my thumbs with sour machine oil. The spindle wasn't just scored with lines; tiny raised brass pins spiraled around its shaft like the comb of a music box cylinder. I dug the notched copper thimble from my pocket, lined its internal teeth up with the spindle's squared tip, and shoved them together. With a dry, tight snap, the two locked into one solid crank. The blueprint was right about the gear count. Now I just need to find where this spindle is supposed to turn.