Replica ZENITH CHRISTOPHE COLOMB, THE BEAUTY OF DARING COMPLEXITY
With this highly sophisticated model christened in tribute to Christopher Columbus, the bold 15th century explorer who was the first to tackle the ocean head on rather than following coastlines, Manufacture ZENITH proudly presents one of the great modern-day horological accomplishments stemming from over five years of intense development.
The decision to name this watch after Christopher Columbus relates to the very nature of this ultra-complex model which addresses one of the key issues that faced this adventurous seafarer and still haunts the contemporary watch industry to this day: how to achieve precision measurements with instruments that are subjected to constant motion that is detrimental to their accuracy. However, this name is not merely a tribute to one of the greatest maritime adventurers of all time; it also points to a historical heritage, as Zenith produced a Lépine chronometer movement at the beginning of the 20th century whose escapement was already known as the “Echappement Colomb” (Columbus Escapement). This 20½‘’’ NVI chronometer was awarded three First Prizes by the Neuchâtel Observatory and an “Especially Good Class A Certificate” from the Kew Observatory, Teddington.
Maintaining precision against all odds
A century or so after Christopher Colombus’ bold feats, maritime navigation was to be considerably improved by the development of a shipboard compass featuring a “Cardan suspension” on gimbals, a type of universal joint in a shaft that enables it to rotate when out of alignment. This system proved particularly useful in keeping the instrument so vital to survival at sea upright even when a ship was pitching and rolling on the waves. While 16th century mathematician Girolamo Cardano after whom the joint is named did not claim its invention, he described it in detail and apparently drew inspiration from a sedan chair made for the Emperor Charles V and featuring an ingenious system cancelling out the slope of the terrain so as to ensure that the sovereign’s chair would remain flat and stable even if a bearer were to stumble!
Subsequently used to equip marine chronometers, this Cardan suspension system has now inspired the Manufacture ZENITH movement design engineers in seeking to compensate for the effects of gravity on the precision of a wristwatch. While the tourbillon was specifically designed for this purpose in respect to vertically-carried pocket-watches, wristwatches move through constantly varying positions and thus required an entirely different approach.
Given the well-known fact that keeping the regulating organ in a horizontal position generates the best possible amplitude of the balance and thus considerably enhances timing precision, Manufacture ZENITH decided to ensure that the regulating organ and the escapement were indeed permanently kept in this position.
This was of course easier said than done however, especially when one considers the numerous challenges of keeping a wristwatch flat in various daily or sporting activities such as driving, golfing, or skippering a boat.
Applying this to a movement beating at the exceptionally high rate of 10 vibrations per second further complicated matters, which does much to explain why a full five years of development have gone into presenting one of the major recent accomplishments in the watch industry. Even the numbers give an idea of the sheer complexity of the task, since this daring complication comprises 166 components, while a tourbillon has approximately 66. The result is the first wristworn timepiece in which the rate is completely independent of its wearers’ movements.
A noble exterior to house a prestigious mechanism
The hand-wound 45-jewel, 36,000 VpH Academy 8804 manual winding movement with 50-hour power reserve, features a unique gyroscopic system ensuring perfect horizontal positioning of the regulating organ. This system consists in a cage composed of 166 parts, 10 conical-geared wheels (with 6 spherical wheels) and 6 ball bearings.
The 45 mm-diameter case comes in a choice of white, rose or yellow gold and is fitted with cambered glareproofed sapphire crystals on both sides, with the Gyroscopic system topped by its own sapphire crystal “dome”. The eminently readable silvered dial is adorned with a barleycorn guilloché motif. The off-centred hour and minute subdial appears at 12 o’clock opposite the gyroscopic cage, while the small seconds are displayed at 9 o’clock and the power reserve on a segment extending from 2 to 4 o’clock. The faceted hands are in blued steel, as are the applied numerals and hour-markers. Finally, this handsome model with its revolutionary interior is secured to the rest with a crocodile leather strap and fastened by an 18-carat gold triple folding clasp.
A shared will to explore uncharted territory
When intrepid navigator Christopher Columbus set his course westwards in an attempt to reach Cathay (China) – rather than eastwards like everyone else at the time – little could he have imagined that his voyage would lead him to the unexpected and epoch-making discovery of the New World. The watchmakers and movement design-engineers of the Manufacture ZENITH undoubtedly sense a feeling of affinity with this determination to do things their own way, and their tireless exploration has led to a discovery also destined in its own way and quite literally to change the very face of time.
Brain candy for tech-lovers
The rating precision of a classic watch varies according to its position. Gravity attracts the escapement components, which do not operate in exactly the same way according to the direction in which they are attracted. The friction between the various components is also different and the amplitude of the balance may be disturbed, causing it to gain or lose. The best position for an escapement is the horizontal position which ensures the best amplitude for the balance and on which gravity is perpendicular to the components and does not therefore disturb their rotation.
The need to improve the precision of clocks for navigation led to the invention of marine chronometers, in which the entire movement is mounted on gimbals and remains horizontal despite the ship’s movements. This was the only way of achieving chronometric precision enabling a reliable measurement of position when at sea by comparing local solar noon with Greenwich Mean Time for example. When it became important to make pocket-watches more accurate, the same means could not be used, because that would have involved placing in the pocket a large mechanism measuring 50 mm.
Working on the principle that a watch in a pocket remains in a vertical position and that only the stem leans to the left or the right, the tourbillon watch was invented. This system does not prevent the position-related flaw from occurring, but instead averages out the flaw over the 4 vertical axes every minute. Since the watch does not move very much, it is adjusted to this particular average. However, as mentioned earlier, the constant vertical position of the balance is not the most favourable.
With the arrival of wristwatches, the positions of the watch were diversified by adding positions with the horizontal dial pointing downward or upward. Classic tourbillons continue to correct 4 positions out of 6 and already enhance precision, although only partially. Inclined tourbillons or gyrotourbillons average out more positions, but this is still the average of several errors, and they are only briefly in a horizontal position. The ultimate step thus lay in adapting the best solution, that of the constant horizontal escapement, to the wristwatch.
To avoid making a huge mechanism, only the part most sensitive to variations in position is mounted on gimbals and thus benefits from a more or less constant horizontal position – as well as a slightly gyroscopic stabilising effect of the balance. It was however necessary to find a system that enabled the two parts of the movement – the one that follows the position on the wrist and the one mounted on gimbals – to remain perfectly coordinated.
This perfect coordination is achieved in an extremely elegant manner by Zenith’s patented 0G system. In this system, a gear system harnesses the rotations of the axes of the carriage and a reverser differential gear instantly compensates for all the relative movements of the various elements.
The cadence of the operation of the gear train indicating the time on the part connected to the wrist movements is imparted by the escapement situated in the carriage, which constantly seeks to find its point of equilibrium determined by gravity. If the watch is moved in such a way as to set the carriage spinning on its axis, the coordination system compensates for this rotation and the hands continue imperturbably indicating the correct time, whatever the speed of the direction of this rotation.
For all these reasons, Manufacture Replica ZENITH considers this system to be the ultimate evolution in comparison to the existing tourbillon systems.