The mechanical solution provided by the London instrument maker Elliott Brothers was this remarkable device: an electrical racing chronograph with tape recorder. It came for sale at German horology specialist Auktionen Dr Crott on May 21, “out of the middle of nowhere in France”, said auctioneer Stefan Muser, with an earlier provenance to the Automobile Club de France (ACF).
The search for recently published information about this complex instrument drew a blank. So did enquiries with the London Science Museum and the Brooklands Museum, birthplace of British motorsport, in Surrey.
However, through a specialist in early electrical clocks, Muser was able to track down an article in the journal Science et Vie from 1922. In it the device is photographed and described in detail.
Time was measured in quarter-second intervals via a chronograph with lever escapement. However, to ensure readings were done without potential for human error, the stopping and starting of the clock was triggered by air-cushioned hoses lying across the track.
As the cars passed over, copper contacts completed an electrical circuit and the precise time was then recorded and printed on a reel of paper.
According to the 1922 text, only two examples of this apparatus existed – one owned by the ACF (seemingly this example) and another used at Brooklands in an era when the 2¾ mile circuit was the testing ground for the fastest cars in the world. It was in 1922 when a 350hp Sunbeam achieved a new land speed record of 129.2mph.
This small piece of motor-racing history (offered together with a blueprint showing the wiring of the electrical system plus associated ACF literature) came for sale in Mannheim with a guide of €7500-15,000. It did not look over-priced when it was bought at the low end of expectations: €7500 (£6800) plus 25% buyer’s premium, by a German client.