I write with a foot in two allied camps; as a member of the AHS and a Curator of Horology at the British Museum. In October last year the AHS Council generously donated sixteen interesting clocks, watches and horological tools to the BM collections. The items had in fact been at the BM since 1973, having been deposited on long-term loan when the AHS left its former London HQ. This conversion to a donation consolidates that loan and upholds one of the core objectives of the AHS which is the support of public collections. Let us look at three of the items.
Firstly, a lantern clock with centre verge pendulum by Johannes Kent of Congleton, Cheshire, late 17th century. Lantern clocks with centre pendulum sometimes had “angel wing” extensions to the side doors to accommodate the arc of pendulum. This clock does not have these, but the side doors (which seem to be later) do not interfere with the action of the pendulum. Unusually for this time, the clock does not have Huygens’s endless winding system, but has a separate drive for each train.
Next, an interesting year-going movement. This was probably housed in a slate or marble case, perhaps something like this. The inscription on the dial is somewhat rubbed and not wholly legible, but it seems to be signed for Edward Watson of King Street, Cheapside, London (working 1815-63) who would have been the retailer for the clock. The movement is stamped to show that it was made by Achille Brocot of Paris. Brocot invented this type of long duration movement in the mid-19th century, employing multiple mainsprings in going barrels to drive the clock. The system has great advantages over using a single large mainspring to achieve a long duration. Smaller springs are easier to make and much easier to remove for maintenance. Also, if one of the five springs were to break it would cause far less damage to the clock than a recently-wound single spring with a year’s worth of driving energy being unleashed.
… and finally, an unusual and incredibly useful screwdriver. It has five slot heads at different orientations enabling access to those awkward screws, such as between the plates of a movement. Right, I’m off to attend to a newly-installed longcase clock which has stopped – an in-situ adjustment of the back cock should do it..!
As with all items in the collections of the British Museum, these items are kept to be made accessible to all members of the public. An appointment to study them can be made by contacting the horological team at firstname.lastname@example.org or by telephone (020 7323 8395).