In 1914, the Kew Observatory in Great Britain granted a “Class A” certificate to a wristwatch for the very first time. This major achievement by a small Rolex watch astonished the world and marked the advent of the modern precision wristwatch.
Until then, such a certification, which attested to the highest chronometric precision, had generally been awarded only to large marine chronometers after extremely rigorous tests. Rolex was the first to prove that a wristwatch could be just as precise as a marine chronometer – something that was scarcely believable at the time. This performance would contribute significantly to the rise of the wristwatch.
On the strength of this success, Rolex would become the world’s largest manufacturer of chronometer-certified wristwatches. The brand perfected the concept of the modern watch in 1926 by inventing a waterproof Oyster case to protect the movement and then, in 1931, by developing the self-winding Perpetual rotor movement. Today, all Rolex Oyster models are officially certified chronometers, the heritage of the pioneering role played by the brand in bringing precision to the wristwatch.
|Certificate by Kew Observatory , 1914|
By obtaining the very first “Class A” rating certificate for a wristwatch from the Kew Observatory near London, on 15 July 1914, Rolex accomplished an exploit that would forever change the destiny of the modern watch. A feat of miniaturized precision, this first chronometer wristwatch met with flying colours the British observatory’s demanding criteria, the most stringent in the world: 45 days of tests, in five different positions and at three different temperatures (ice-cold, oven-hot and ambient).
For the first time in history, a wristwatch fulfilled the requirements expected of the best marine chronometers. These navigation instruments, whose precision was used to determine the position of ships at sea (longitude), could not deviate by more than a few seconds per day without putting the safety of the ships at risk. The Rolex wristwatch chronometer certified by Kew 100 years ago recorded an average daily rate of only +1 second.
|A Rolex wristwatch comparable to the one certified as a “Class A” chronometer by Kew in 1914|
The man behind this feat was Hans Wilsdorf, who founded Rolex in 1905. By obtaining this first chronometer certificate from Kew, he demonstrated that, in terms of precision, a small wristwatch made by Rolex could rival the best of timepieces – including pocket watches, which were the norm at the time. In those early days of the 20th century, no one had yet managed to design a truly reliable and precise wristwatch. Wristwatches were not favoured at the time, as the small mechanism could not compete with the regularity and reliability of the larger pocket watch movements.
However, since the beginning of his career, Hans Wilsdorf had been firmly convinced that the wristwatch would be future of the watchmaking industry. He devoted the energy of his youth to eliminating all the weak points of the wristwatch. The quest for precision was his first objective. This visionary entrepreneur was firmly convinced that precision was essential to secure the acceptance and popularity of the wristwatch.
Nearly two centuries after John Harrison designed the first marine chronometer, Rolex targeted equal precision for a wristwatch. The first success came in 1910 when the brand succeeded in obtaining a chronometer certificate for a small watch from the Official Watch Rating Centre in Bienne, Switzerland. In 1914, Rolex designed and produced a chronometer wristwatch whose precision equalled the most sophisticated measuring instruments of the era and had it certified by the Kew Observatory. Its performance was unheard of; endorsed by the most prestigious official observatory in the world, it would contribute decisively to the rise of the wristwatch.
Until then, making the wristwatch into a reliable, robust, high precision device had been the stuff of utopian dreams. But Hans Wilsdorf demonstrated that precision in a small format was not only conceivable but also achievable. This distinction by Kew was an official recognition of the highest world-class quality for Rolex and held the promise of a bright future for the wristwatch. From then on, to maintain its leading position in the manufacture of high-quality precision wristwatches, Rolex made it a point of honour to develop mechanical movements that were certified as chronometers by observatories and official watch rating centres.
|Letter from British Horological Institute to the founder of Rolex on the subject of the record Kew Certificate|
While officially certified by chronometer certificates, the precision attained by the Rolex wristwatch remained much more vulnerable to shocks, dust and humidity than that of pocket watches. Therefore, Rolex’s next objective was to design a perfectly waterproof case to protect the movement and maintain its certified precision. This was accomplished in 1926 with the invention of the Oyster, the world’s first waterproof wristwatch, thanks to an ingenious patented case system featuring a screw-down bezel, case back and winding crown.
The name, Oyster, was inspired by its capacity to remain indefinitely submerged in water without risk of damage. It was not only waterproof, but also dustproof, for dust is a formidable enemy of watch movements. To further perfect its watches, Rolex developed in 1931 the Perpetual self-winding system, which winds the mainspring via the action of a free rotor driven by wrist movements. There was no longer a need to wind the watch manually with the winding crown, a critical point for maintaining water proofness. This self-winding system, also patented, ensured a constant power reserve and regularity of rate.
The Rolex Oyster Perpetual thus accumulated three fundamental qualities: it was precise, waterproof and self-winding. These advantages would provide an extraordinary stimulus for the Swiss watchmaking industry and the contemporary mechanical watch.
A true pioneer in chronometer wristwatches, Rolex made certified precision its signature. By the early 1950s, Rolex had manufactured nearly 90 per cent of all chronometers officially certified in Switzerland since 1927 — the year specific criteria for wristwatches were introduced. When, in 1951, the regulations changed and it became compulsory to obtain chronometer certification from an official body, Rolex went further and made sure its movements obtained certificates bearing the citation “particularly good results”.
This distinction gave rise to the famous phrase still inscribed on Rolex dials today: “Superlative Chronometer Officially Certified”. Since the creation of the COSC (Swiss Official Chronometer Testing Institute) in 1973, special citations are no longer given on the certificates. But the signature on Rolex dials remains as a reminder that since the early 20th century, Rolex has played a central role in the development of the modern precision watch. The brand’s leadership in chronometric precision continues to the present day, as Rolex is the largest manufacturer of chronometer-certified watch movements in the world.