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Plot and as with

Best fit to data (blue line). Reference gradient (red lines):-605ms/day/deg C.
this is for an uncompensated steel pendulum -605ms/day/C (we hope to acheive within 10ms/day/C with compensation)

Comments (see all | edit)

16 Nov 2010 [21:15]
Correction of -15 seconds for a reverse pigeeon event. It seems that the removal of the weights on the gravity arms (17h30 30 Oct) means that the gravity arms jump more easily, as observed when the maintaining weight is engaged alongside the main driving weight. A Pigeon on the hands at hh:15 will have the same effect as a maintaining weight.
16 Nov 2010 [15:35]
ADJUST: +800 ms/day to 29500 It is clear that the temperature compensation has gone wrong [link] . Quite possibly when we adjusted the regulation nut we managed to jam something in the set of steel/zinc concentric tubes that make up the pendulum [link]
11 Nov 2010 [08:00]
TC works staff were checking out clearance in the pendulum case - they must have touched the pendulum
09 Nov 2010 [13:25]
ADJUST: -500 ms/day to 28700 Now that the pendulum is swinging nicely we can see that the temperature compensation is not ideal - sticking somewhere?

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Interval between data points: seconds [either 3 seconds (weather data is duplicated) or multiples of 60 seconds (all data is averaged)].

Contact:, Trinity College, Cambridge