23:4123:41, 12 March 2009diffhist+3,972
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Observatory chronometer
←Created page with 'A very rare and very accurate form of Chronometer is the Observatory Chronometer. Once mechanical timepiece movements developed sufficient precision to allow for …'
23:4123:41, 12 March 2009diffhist+3,972
N
Observatory chronometer
←Created page with 'A very rare and very accurate form of Chronometer is the Observatory Chronometer. Once mechanical timepiece movements developed sufficient precision to allow for …'