Six Inventions are a rarity

Great ideas are often best expressed numerically: Four Noble Truths, Ten Commandments, 31 Flavours. In the world of Greubel Forsey one speaks of The Six Inventions.

Three - Double Tourbillon 30°, Quadruple Tourbillon and Tourbillon 24 Secondes - have been embodied in watches of such excellence that the Greubel Forsey name is synonymous with the refinement of the tourbillon. Three others remained in evolution - Binomial Balance Spring, Différentiel d'Egalité and Double Balancier - until this year's SIHH, when Double Balancier and the Sixth Invention skipped ahead to emerge as a commercial reality in Double Balancier 35°.

The object of the Double Balancier regulating system is to minimise the effects of gravity and thus achieve more precise timing by driving two inclined fixed-oscillators through the spherical differential to give the average of their rates.

Although some previous limited edition models in 2009 and 2011 were moving in this direction, in the new watch the oscillators and escapements are tilted and locked at 35 degrees. A 43.5mm case in 18ct white gold has a silver dial with the mechanism visible in two windows in the lower half, and the second-hand window between them. There are only six watches in this edition, which has been described as "a true first in horology".

"For Greubel Forsey, horology and artistic creation are inseparable", and are part of the company's manifesto. One hesitates to say "brand", as Greubel Forsey tends to rise above blatant marketing and concentrate its efforts on exploring new horological territory for its own sake. It has elevated watchmaking to an art form which is an end in itself.