Derek Pratt – flying tourbillon with remontoir and detent escapement

People · · by Christian Bissener


Oval silver pocket watch by Derek Pratt with white dial, Roman numerals and moon phase, held in a hand

Derek Pratt was the watchmaking mastermind behind Urban Jürgensen from 1979, when Peter Baumberger took over the house. The two had worked together before, when Baumberger dealt in antique watches. They remained together at Urban Jürgensen until Pratt’s death in 2009; Peter Baumberger died a year later.

Probably the most important timepiece Pratt built is the oval flying tourbillon with remontoir, detent escapement and Réaumur scale. From the architecture of the movement to its finishing and complexity, it is the epitome of pure watchmaking. The dial is hand-guilloché and hand-engraved, and every part of the watch is made by hand – something that is hardly done any more, except by one or two independent watchmakers who still build without CNC.

Open silver oval pocket watch showing the exposed tourbillon cage and a gold-finished movement
The oval flying tourbillon with remontoir, seen through the open case

Open silver oval pocket watch showing the gold movement and tourbillon, held in a hand
The movement

Pratt was a good friend of George Daniels and helped him in the development of the co-axial escapement. Of the two, we prefer Pratt’s finishing and style, and the difference is plain when a Pratt movement is set beside one by Daniels. Consider two recent auction results: the Space Traveller I, sold at Sotheby’s in July 2019 for £3,615,000, and the Grand Complication, sold at Phillips in May 2019 for CHF 2,420,000. By that measure the Pratt oval tourbillon deserves to be valued at least as highly.