The Symbiosis of Time
Inspired by our “cosmic clock”, the earth, the True North Perpetual is a truly unique achievement offering an exceptional set of useful and fascinating functions, protected by an international patent and several registered designs. It is also the first timepiece capable of indicating true solar time in a given place and the true geographical North.
The mechanical hand-wound 7-day power-reserve movement driving this unprecedented model is distinguished by the revolutionary technology of its gears featuring elastic toothing, and a three-level going-train comprising interior toothing. Its generous autonomy is particularly important when you consider the wide range of indications it provides. Apart from its primary role of showing and keeping time, the True North Perpetual has a whole lot more to show us about the world and indeed the universe…
Highly practical perpetual calendar: it can be tiresome to have to keep adjusting the date to months of varying lengths and to the leap-year cycle. This function does it all for you, since it is mechanically programmed to take account of all these variations and will need no adjustment until the year 2100, when a quirk in the Gregorian calendar will require an adjustment.
Ultra-accurate moon phases: traditional moon-phase displays fairly quickly show a discrepancy with the celestial reality. More precisely calculated on a 29.5-day lunar cycle, this moon phase will lose no more than one day in 122 years.
Calculation-free double equation of time display: the fluctuating difference between true solar time and standard civil time as we know it is called the equation of time. The rare models providing this display generally required the user to perform a calculation each time he wishes to determine the equation of time. To enhance the user-friendliness of this sophisticated instrument, Arnold & Son have made it capable of doing all the arithmetic for its lucky owner, who may simply read off this indication either on its dedicated segment, or on the “running equation” solar hour scale around the outer mobile dial ring.
Unique true solar time indication: The operating principle of this sophisticated watch is based on the obvious fact that our mean civil time (as shown on our watches) is valid throughout a given time zone. On the contrary, true solar time is different for each longitude and depends on the earth's position around its elliptical orbit. The user of a Arnold & Son True North Perpetual may read off true solar time in his given location, provided he makes three specific corrections: setting the watch to standard or “winter” time; adjusting for longitude; and correcting the running equation of time. This combination of optimal functionality and visually appealing clarity is made possible by a 24-hour solar hand and a triple dial composed of a large fixed central dial and two mobile dial rings.
Reliable true geographical North: Once a day when the sun-tipped solar hand points to true solar noon, one can experience a unique thrill no other watch can procure, simply by pointing this 24-hour solar hand in the direction of the sun. Independently of the errors induced by magnetic fields, one's position within the Northern hemisphere or the date, the mobile outer dial ring will then indicate true geographical North.
For people who like to feel at home on both on our planet and within our solar system, the True North Perpetual from Arnold & Son offers an inimitable way of keeping their bearings in any circumstances!
Case: 45 mm-diameter, white gold and a limited edition of 50 in white gold and 50 in pink gold. See-through case-back secured by 12 screws.
Movement: Exclusive mechanical hand-wound 7-day movement calibre A1794 with 168-hour power reserve.
Functions: Hours, minutes, moon phase (calculated a 29.5-day lunar cycle), perpetual calendar, equation of time and true solar time.
Glass: Sapphire crystal
Strap: Crocodile strap with folding buckle clasp.
Water resistance: 30 metres (100 feet)