ROSS-TYPE COMPOUND MONOCULAR BAR LIMB MICROSCOPE-achromatic condenser fitting.

A rack and pinion-focused achromatic condenser fitting sits on a plate that fits under the stage, sliding in from the front. The plate is held in place by two tabs. The screw in front of the plate has a rod machined into the end to fit into a hole in the front of the stage; the screw can be adjusted to center the fitting in the X-axis. It also serves to provide a third point securing the plate to the bottom of the stage.