Striking variant
Richard Willmott's letter and photographs in February's edition reveal a fascinating variant on the normal strike control. I cannot with any authority answer his question about the origin of the clock, though I would guess it's Germans if I had to, remembering that the French/German border sometimes moved. But I would point out that the strike control mechanism has a lot in common with a French variant I have come across. In twenty years at the bench I have only seen two of these French ones. In both instances, the unusual strike control accompanied unusual barrels, in that the barrels were removable.
The design is well covered in an article in Clocks Volume 20 No 6, June 97, p20, by Anthony Whitty.
In each design the stopping of the strike sequence is determined by the turning of a slower arbor in that train. In the French case this is the intermediate arbor, and in Richard Willmott's clock it is the pin wheel arbor. In one respect, the French design seems less satisfactory to me, having to depend on return springs and friction-tight joints, which I would expect to be the cause of problems - though I might be wrong. It also lacks the repeat facility, though this could be added if required (the snail would have to be stepped).
The question I find myself asking is: what advantage did the designer see in this unusual departure from common practice? In both these designs, I think the answer is that the striking would have been accompanied by less extraneous mechanical noise than otherwise. This is because these designs have no rack hook whose clicking noise is often heard through the striking. I suspect Richard Willmott's clock gives an audible thud when the rack drops, whereas the French design would not.
I have been developing a presentation on unusual strike control, and have so far given it to two branches of the BHI. Each time, it seems, there are more variants out there that come to light. I would welcome information from any readers about unusual designs they have come across.
David Churchill, UK
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