Lot 56

Parkinson & Frodsham

A fine precision hunting case pocket watch with "DUO IN UNO" balance spring, 30h power indicator and spring detent escapement

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The "duo-in-uno" balance spring allows a reduction in the height of a helical spring, thus saving space in the height of a pocket chronometer movement. In fact, it is a flat balance spring converting into a cylindrical spring. It was first introduced during the 1862 Great Exhibition in Kensington, London, at the Charles Frodsham stand.
According to Frodsham, it "almost certainly guarantees the most accurate performance in all positions with a perfectly poised balance" (exhibition catalogue, p. 22).
This type of balance spring was supposedly invented by Mr. Mairet of Baker Street and presented during the 1862 exhibition by Charles Frodsham and Mr. McLennan; However the design had already been used by Arthur Paul Walsh since circa 1860.

The company of partners William James Frodsham (1775-1850) and William Parkinson had its offices at 4, Change Alley, in London and specialised in the production of pocket and marine chronometers. Several expeditions were equipped with their watches. Around 1847 Frodham handed the company over to his sons George and William. Parkinson & Frodsham maintained the clocks in Buckingham Palace and was appointed clockmaker to the King, the Princes of Wales, and Queen Alexandra.