To celebrate the feat, Rolex published a full-page advertisement on the front page of the Daily Mail for every issue for a whole month proclaiming the watch's success during the ten hour plus swim. In 1927, British swimmer Mercedes Gleitze swam the English Channel with an Oyster on her necklace, becoming the first Rolex ambassador. Īs a demonstration, Rolex submerged Oyster models in aquariums, which it displayed in the windows of its main points of sale. The watch featured a hermetically sealed case which provided optimal protection for the movement. The original patent attributed to Paul Perregaux and Georges Peret, that allowed the watch to be adjusted while maintaining protection from water ingress was purchased - not invented - by Rolex and heavily marketed. To address this problem, in 1926 a third-party casemaker produced a waterproof and dustproof wristwatch for Rolex, giving it the name 'Oyster'. With administrative worries attended to, Wilsdorf turned the company's attention to a marketing challenge: the infiltration of dust and moisture under the dial and crown, which damaged the movement. In 1920 the company's name was officially changed to Montres Rolex S.A. In 1919, Hans Wilsdorf moved the company from England to Geneva, Switzerland because of heavy post-war taxes levied on luxury imports and high export duties on the silver and gold used for the watch cases. In November 1915, the company changed its name to Rolex Watch Co. He also thought that the name 'Rolex' was onomatopoeic, sounding like a watch being wound.

Wilsdorf wanted the brand name to be easily pronounceable in any language, and short enough to fit on the face of a watch. He opened an office in La Chaux-de-Fonds, Switzerland. In 1908, Wilsdorf registered the trademark 'Rolex', which became the brand name of watches from Wilsdorf and Davis. The earliest watches from Wilsdorf and Davis were usually hallmarked 'W&D' inside the caseback. These early wristwatches were sold to many jewellers, who then put their own names on the dial. Wilsdorf and Davis' main commercial activity at the time involved importing Hermann Aegler's Swiss movements to England and placing them in watch cases made by Dennison and others. Alfred Davis and his brother-in-law Hans Wilsdorf founded Wilsdorf and Davis, the company that would eventually become Rolex S.A., in London, England, in 1905.

Value of old longines watches