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"The long lever D is pressed to one side by the screw F, and is thus turned round the in E. On the tube very near to pin E is cylinder C, which by the action of the screw F is very slightly raised or lowered." —Encyclopaedia Britannica, 1910

Swift and Son Micrometer Adjustment Lever for Microscope

"The long lever D is pressed to one side by the screw F, and is thus turned round the in E. On the tube…