iris diaphragm lever: moving the lever to the left increases the light; moving the lever to the right decreases the light.
forward/backward stage control: moves the mechanical stage holding the slide forward and backward.
left/right stage control: moves the mechanical stage holding the slide left and right.
coarse focus: turning the knob away from you raises the stage; turning the knob towards you lowers the stage.
fine focus: turning the knob away from you raises the stage; turning the knob towards you lowers the stage. 

Gary E. Kaiser, Ph.D.
Professor of Microbiology
The Community College of Baltimore County, Catonsville Campus
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