Sentence Examples with the word rack and pinion

Since, however, only relatively low powers are now employed, the ordinary rack and pinion movement for focusing suffices, and for the illuminating the object only a mirror below the stage is required when the object is transparent, and a condensing lens above the stage when opaque.

The rough adjustment of the microscope can be made by a rack and pinion F; and the fine adj ustment by the screw G.