Hello Antiquers! We have this unusual Bausch and Lomb piece, not sure what its exact function is. It has a large wheel on the right that is manually operated via a handle, the cranking of which moves the left portion up and down, and in turn a small disc moves with it. It is close in proximity to a fixed part of the machine which appears to have a small metal wedge that is meant to be ground down? Any thoughts? Thanks a lot!!
Microscope slide cutter probably. https://www.worthpoint.com/worthopedia/antique-bausch-lomb-optical-rotary-1846846744
More generally known as a rotary microtome. It slices things really thin for inspection under a microscope. Dennis