Note that the coarse focus utilizes fusee chain drive. In How to Work with the Microscope, lectures by Lionel Smith Beale-1861, it is implied that some microscopes designed by Samuel Highley were manufactured by William Ladd, London who first introduced the use of a fusee chain mechanism in 1851.

Illustration from the British Medical Journal 1867

This microscope was found cased with a separate  Aquarium Microscope which uses the same optics.