[time-nuts] Re: Ship's clocks @ The Royal Society

[Jim Harman]

Also at 3:52 Adam says one metal expands and the other contracts with
temperature. Actually they both expand but at different rates. The
"gridiron" pendulum developed by Harrison is arranged so that the
expansions cancel out and its length and thus its period stays constant
over a range of temperatures.
https://en.wikipedia.org/wiki/Gridiron_pendulum


>
--Jim Harman