There are a couple of old clocks in the Old Observatory, mainly in the entrance hall. The important clocks will be covered individually.

[] It is not sure in what year the main clock was installed, apart from the fact that it used to be an electrical Loebner movement that was later replaced by the current one. The earliest mention of this clock that Alex found is in the 1892 annual report¹⁾ where the Loebner movement is said to have been faulty and therefore cleaned. One year later director Bakhuyzen complains about the clock again²⁾, saying that it takes a lot of maintenance to keep the time correct within a few seconds and that the face of the clock gets covered when the error is too big. He ends the paragraph by saying that it is in public interest to fix the clock, as it is their source for the correct time, but there currently is no money.

[] In September 1896 the movement was replaced by a new Swiss electric movement by Peyer Favarger³⁾. It was thoroughly tested and slightly modified by the observatories 'Custos-mechanicus' to ensure proper beats of the second hand. This movement has remained in the clock ever since and has faithfully given the time to astronomers and visitors alike and hopeful will remain doing so for many more years to come.

manual: clockmanual.pdf

Here it talks about the new movement: http://adsbit.harvard.edu//full/1896VeLdn..32....1V/0000004.000.html

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