A TWO-DAY SURVEY CHRONOMETER WITH 24-HOUR DIAL AND HALF SECOND ELECTRIC CONTACTS

THOMAS MERCER, NO. 15430, CIRCA 1940

细节

A TWO-DAY SURVEY CHRONOMETER WITH 24-HOUR DIAL AND HALF SECOND ELECTRIC CONTACTS
Thomas Mercer, No. 15430, circa 1940
The 24-hour silvered dial signed THOMAS MERCER MAKER TO THE ADMIRALTY, Eywood Rod. ST. ALBANS, Arabic hour and five minute intermarkers, subsidiary seconds dial (cut away for access to electric contact detents) and up-and-down dials, blued steel hands, the movement bowl and case fittings numbered 15430, Earnshaw escapement, Mercer flat strip steel detent to side of banking block, cut bimetallic balance, circular heat compensation weights, palladium helical balance spring, external stop/start assembly, in drum-shaped aluminium case
150 mm. overall diam.

拍品专文

This chronometer was made in 1940 and was issued to the Ordnance Survey department. It was used in conjunction with a chronograph whereby time of astronomical observations could be permanently recorded on paper tape.

The chronometer is wound clockwise through the dial.