C. Allix & P. Bonnert,Carriage Clocks, Their History and Development, Woodbridge, 1974, p.258, pl.IX/26
R.V. Mercer, Edward John Dent and His Successors, London, 1977, pp.341-342
D. Roberts,Carriage and Other Travelling Clocks, Atglen, 1993, p.306, figs.21-6 a,b, pp.312-315, figs.21-14 a,b,c,cd & 21-15 a,b,c,d
DENT NICKEL CHRONOMETER CARRIAGE CLOCKS
Nickel (also known as 'German silver') carriage clocks by Dent are extremely rare. Including the present example, it is believed there are just eight such clocks. Among the finest carriage clocks ever made by the Dents, all have chronometer escapements. However, just one other is known to have a prismatic balance. The following clocks are known:
No.1458. Signed: F. Dent, 61 Strand & 34 Royal Exchange, London. Features: spade hands, foliate mask, polygonal handle
John Carlton Smith advertisement, Antiquarian Horology, December 1982, p.519
No.1567. Signed: Dent, 61 Strand & 34 Royal Exchange, London. Features: spade hands, foliate mask, polygonal handle, with presentation inscription, timepiece, Type B prismatic balance
Keith Banham advertisement, Antiquarian Horology, Autumn 1979, p.463; Phillips London, 16 October 1980, lot 61; Roberts, p.306
No.14806. Signed: Dent, London. Features: moon hands, foliate mask, split handle, quarter striking, Dent patent double staple balance
Christie's London, The Vitale Collection of Highly Important European Clocks, Part II, 26 November 1996, lot 209; Christie's London, Magnificent Clocks, 15 September 2004, lot 26
No.14880. Signed: Dent, London. Features: moon hands, foliate mask, split handle, quarter striking, Dent patent double staple balance
Allix & Bonnert, p.258
No.15956. Signed: E.J. Dent, London. Features: fleur-de-lys hands, engine-turned mask, split handle, striking and repeating, Dent patent double staple balance
No.17783. Signed: Dent, London. Features: moon hands, foliate mask, split handle, striking and repeating, alarm, Dent patent double staple balance
No.25712. Signed: Dent, 33 Cockspur Street, London. Features: moon hands, engine-turned mask, split handle, striking
An advertisement by E. Dent & Co. from c.1873 reproduced by Derek Roberts (p.308) shows that carriage clocks such as this were the most expensive produced by the company: 'Chronometer time-piece, finest quality, in German silver or dead-gilt case...60 guineas.' To put this into perspective, the same price list gives a range of 20-30 guineas for a comparable clock with lever escapement and a French carriage timepiece would have cost 6 guineas.
All the Dent nickel carriage clocks share common design features, with simple moulded cases exclusive to the type and white enamel chapter discs with a seconds ring at XII, but with certain variations between them. Some have electroformed foliate dial masks and others have engine-turned masks; some have 'splitting' handles and others have polygonal handles. The deep dial decoration of the present clock is seen on other fine English carriage clocks of the period, including examples by both McCabe and Dent, and was achieved by a process patented by Elkington in 1840. The raised design is effected by engraving a design into the mould (matrix) onto which electroplating has taken place (Roberts, p.355).
THE PRISMATIC BALANCE
The rarest feature of the present clock is undoubtedly its use of a prismatic balance. First developed by Edward John Dent in 1851, with this form of temperature compensation the form of the balance rim is altered, as Dent wrote to Airy, the Astronomer Royal: 'I suggest...to alter the shape of the steel in the balance rim from that of cylindrical form and having the steel and brass of the same figure, and is, to make the steel of an angular (or prism) shape...' (Mercer, p.341). Three forms of prismatic balance (A-C) were designed and No.1392 employs Type B, developed in 1852.
The death of Edward John Dent in 1853 led to a division of his business between his two stepsons, Frederick William Rippon and Richard Edward Rippon, who were required to take Dent's name. Frederick Dent continued the business from 61 The Strand and 34 Royal Exchange and Richard Edward Dent at 33 Cockspur Street. Upon the death of Frederick in 1860, his sister and brother-in-law took over the business, under the new title E. Dent & Co. (Allix & Bonnert, pp.250-251).