Lot Essay
Except for subsidiary tidal dials placed above rather than below the chapter ring, the present clock corresponds to the design of the 18th century popular scientific writer and inventor James Ferguson. According to an article by John R. Milburn, 'James Ferguson's Tidal Clocks, 1764-1770,' Antiquarian Horology, Summer 1977, pp. 331-335, a clock fitting this description was built c. 1765, but the present whereabouts of the clock are unknown. The present clock is interesting in this regard because the association of Eardley Norton with Ferguson is documented in a contemporary account of the four sides astronomical clock built for George III, also in 1765. This clock is presently in the collection at Buckingham Palace and incorporates another type of Ferguson tidal dial. Another clock by Norton is illustrated in M. Harris and Sons, A Catalogue and Index of Old Furniture and Works of Decorative Art, n.d., part III, p. 385.
Whether the present example is the "missing" tidal clock can only be matter of speculation, particularly since the dials are in a different position and the wheelwork consequently modified from Ferguson's drawings. The placement of these dials above the chapter ring does make the operation of the tidal shutter and bell simpler mechanically and would have been a logical design alteration in the course of manufacture.
Whether the present example is the "missing" tidal clock can only be matter of speculation, particularly since the dials are in a different position and the wheelwork consequently modified from Ferguson's drawings. The placement of these dials above the chapter ring does make the operation of the tidal shutter and bell simpler mechanically and would have been a logical design alteration in the course of manufacture.