Article

The influence of barometric pressure on watch and chronometer rates

December 2002
British Journal of Applied Physics 4(12):379

DOI:10.1088/0508-3443/4/12/307

Authors:

Experiments are described in which the rate and arc of a high quality watch and a marine chronometer were observed at a number of pressures from zero to 760 mm of mercury. Lack of isochronism can cause pressure variations to affect watch rates differently at different states of winding or in different positions, but fairly consistent values for the pressure coefficients can be derived if allowance is made for change of arc using the rate/arc relationship observed at normal pressures. The observed pressure variations with constant arc are briefly discussed.

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