Little and large

It is good that if I need an emergency blip, I can always fall back on clocks. I left work early having finally succumbed to the heavy cold that everyone else has had. These two clocks are both French and both made around 1900. The larger clock is around 30 cms tall and is a called a Four Glass clock, not surprisingly because of its four glass sides. It also has a mercury compensated pendulum. The idea is that if the weather is warmer and the pendulum lengthens fractionally due to the expansion of metals, the mercury in the tubes will also expand upwards and thus the effective length of the pendulum will remain the same and the timekeeping will not alter. The same principle would apply in cold weather. It is a nice idea but I am not sure it makes much difference in practice.

The little clock is a mignonette (little sweetie), the smallest size of carriage clock. The carriage clock is so called, not because it was used in carriages (though it may well have been) but because it was the first clock that could be carried easily, not having a swinging pendulum. Napoleon issued them to his officers.