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"The micrometer box, and of course with it the whole system of spider webs, is moved by the screw s, whilst the measuring web is independently moved by the screw S." —Encyclopaedia Brittannica, 1910

Repsolds Micrometer Box for Telescope Cape Observatory

"The micrometer box, and of course with it the whole system of spider webs, is moved by the screw s,…