"Quick Change" Gears
Mighty slick, if you ask me
We see these fine patented gears from time to time on various 19th Century guitars. In those days, virtually all geared tuners were fitted to guitars with slotted headstocks. Here, they appear on a completely unmarked guitar of unknown provenance.
All brass construction, with steel "worm shafts" and natural bone buttons
To string up, you'd pull the knurled knob out, disengaging the gear, and simply wind up the string on the post
Then, simply press the knob back in place, where it keys into one of four slots, and tune via the gear mechanism.