Arnold & Son Tourbillon Chronometer N°36: In The Footsteps Of James Cook

John Arnold, a true man of the Enlightenment, needed to keep a watchful eye on every innovation proposed by the designers of his day. As a trained technician, he knew that the simpler the movement and the more efficient the escapement, the greater the likelihood of the timepiece being easy reproducible and competitively priced.

Building on these reflections and entering into the competition in the 1770s alongside other brilliant watchmakers to create the ultimate timekeeper, Arnold succeeded in just one year in developing three totally original on-board chronometers. By comparison, it had taken Larcum Kendall two years to produce its K1, a copy of the H4, the model that had earned John Harrison the 20,000-pound prize awarded by the Board of Longitude.
 

At the time of their launch, his detractors were highly critical, as absolute precision was still lacking, but its ease of manufacture and reproducibility paved the way for his reputation. Virtually the only one in the market and capable of fast production, he sold his products for princely sums to seamen or scientists eager to possess their very own instrument capable of keeping accurate time aboard their ships or on long expeditions.

With a virtual monopoly on the situation, he thus ignored the criticism from watchmakers who were unable to rival him. However, in order to perfect the ideal mechanical arrangement, the one instrument that could satisfy mariners' needs, Arnold would have to try out more new types of escapements, and invent isochronous balances and balance-springs that were insensitive to temperature variations. For this reason, he developed many prototypes, each one different from the next, living off his sales which he sold in order to make a living (or which his customers begged him to sell).
 

In homage to its first historical chronometer, Arnold & Son decided to create the Tourbillon Chronometer no.36 wristwatch as a tribute to the first historical instrument of its kind. In accordance with classic British watch construction, the instrument's calibre has been built in such a way as to ensure that each mobile part (wheels or pivoting elements) can be mounted in their own bridge (no less than 13 in total), which the workshop craftsmen then cuts away aesthetically to alleviate the visual weight of the construction. The architecture ultimately allows the viewer's gaze to delve deep into the very heart of the mechanical arrangement and obtain glimpses of some of the components inspired by those originally used by the founder of this tremendous undertaking in the 18th century.
 

Clearly, such an exquisite gem required a tourbillon cage. One thing that is often overlooked is that the first tourbillon made by Abraham-Louis Breguet in the early 19th century was, in fact, based on Arnold's marine chronometer (no. 11 built in 1770 with pivoted detent, then modified to accommodate the tourbillon cage fitted with Peto's cross-detent). Peto was Arnold's closest friend and even sent his son to train with the watchmaker in 1792. In this construction, with its manually-wound A&S 8600 calibre developed entirely in-house, the cage weighs a few fractions of a gramme and comprises around 58 parts.
 

This highly accurate regulating organ carries the required COSC certification. Likewise, the movement boasts a level of finishing commensurate with that practiced back in the time of the company's founder. Thus, in order to replicate the hand-frosting or grainage so characteristic of mercury-gilded parts, the manufacture finely sandblasts the surfaces. The red gold version sports a grey NAC treated bottom-plate and palladium-plated bridges, while the steel model carries NAC-treated bridges and a black DLC bottom-plate, which was deemed a more contemporary finish. Similarly, for the sublime finishing touch, the bottom-plate features the traditionally mounted jewels in polished white gold chatons, while the screws are also treated in the traditional manner, and the wheels in the gear train driven by the double barrels, guaranteeing a power reserve of 90 hours once fully wound, are embellished with circular satin-finishing and their edges are chamfered and polished. 
 

A splendid study in symmetry, the Tourbillon Chronometer no. 36 is first and foremost a masterpiece of fine watchmaking dedicated to scrupulous accuracy. Symbolically, it reminds us that the English watchmakers were the first to focus on pure precision and that John Arnold was the first watchmaker in the world to understand the importance of producing timepieces that were not only accurate, but also easily reproducible to satisfy the many mariners needing to pinpoint their position at sea both easily and efficiently. With its dynamic approach and its austere appearance nonetheless harbouring some intricate complications, this piece at once lives up to the name it carries and pays a worthy tribute to English watchmaking, which, let it not be forgotten, dominated the industry throughout the 18th century and a good part of the 19th.