Emilio Segrè Visual Archives

More than 30,000 photos of scientists and their work

Mount Wilson Observatory F8

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Mount Wilson Observatory F8

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Image title: 
Large ruling engine at Mount Wilson Observatory
Credit line: 
AIP Emilio Segrè Visual Archives

Large ruling engine at Mount Wilson Observatory. The 1200-tooth spacing gear at the left is driven by an inclined worm. A shock-free iterative cam rotates the worm once per cycle. Pitch of the main screw is 2mm. The weight of the grating carraige is mainly supported by mercury in tanks flanking the screw. The diamond carriage rests on four flat-topped rails.

Photo date: 
circa 1930
Original format: 
1 photographic print (black and white; 9.5 x 7.5 inches)
Mount Wilson Observatory