Bentley Earth Driven Clock 

  A very rare Bentley Earth Driven Clock
in superb Mahogany Case with Bevelled Glass door

A picture of the Bentley clock and a description from Alan and Rita Shenton’s, Collectable Clocks book,  appears below

This master clock has the unusual distinction of having been designed for use with an earth battery (as had the earlier clocks of Alexander Bain).  The energy driving the clock is obtained from a zinc carbon couple buried 3-4ft deep and 1ft apart in moist soil, which is said to provide a potential of approximately 1 volt at the clock terminals.  The example in the Museum and Art Gallery of Leicester ran for forty years without attention on its original installation before being serviced in 1950.  A more conventional modern battery can, however, be substituted!  The patent for this clock was taken out by Percival Arthur Bentley in 1910 with the Bentley Manufacturing Company being formed shortly afterwards in order to commence their production.  The factory was situated at Forest Gate, Clarendon Park Road, Leicester.  Unfortunately the outbreak of the First World War halted the manufacture of this clock in September, 1914, but the firm moved to the Queens Road Factory, also in Leicester and undertook heavy commitments to help the war effort.  The manufacture of clocks was not reintroduced and the firm was eventually absorbed into the Clore Group.  This particular example is in a handsome, well made mahogany case, bevelled glass to the door, and a silvered skeletonised dial and subsidiary seconds dial.  One other example is known in a superb shaped mahogany case, while others have been seen identical to that in the illustration but in oak.  Two small plates appear below the contact mechanism one carrying the words ‘Earth Driven Electrical Clock No…’ while the other states ‘Bentley’s Mf. Co. Leicester, England’ together with the patent numbers and dates (Patent 19044/10, 3236/12 and 8464/13).  There are some minor variations in the movements but as these are rare clocks there is no merit in being fussy.  In common with many manufacturers, number of the movements did not commence with No. 1 and it is doubtful if more than about seventy were ever manufactured.  Further details on these clocks can be found in the article entitled ‘The Earth Driven Clock’ by Dr. F.G.A. Shenton which appeared in the December, 1972, issue of Antiquarian Horology.  Extremely rare clocks and although they do not play such as important role in the evolution of electrical horology they do seem to compete in scarcity and value with a Bain master clock if in a handsome case.

This clock has now been sold