Rolex bought the front page of the Daily Mail

A watch on a ribbon

On 7 October 1927 Mercedes Gleitze became the first British woman to swim the English Channel, at her eighth attempt and after 15 hours and 15 minutes in the water, watched by an observer representing the Channel Swimming Association's predecessor committee.¹ Days later a doctor, Dorothy Cochrane Logan, swimming under the name Mona McLennan, claimed a faster crossing and collected a prize of 1,000 pounds from the News of the World. On 17 October Logan told the paper's editor that she had faked the swim to show how easily a Channel crossing could be claimed without independent observers, and on 7 November she was fined 100 pounds for perjury. She had been in the water about four hours and spent the rest of the crossing on the support boat.¹ The admission cast doubt on other recent claims, Gleitze's included.¹

Under pressure from the media she agreed to swim again, in water much colder than when Channel swimming is normally attempted.² She entered at Cap Gris-Nez at 4.21 on the morning of 21 October 1927³ and was lifted out seven miles short of Dover after 10 hours and 24 minutes, by then slipping in and out of consciousness.¹ She did not reach England. Her endurance of the cold convinced the doubters, and the October record was allowed to stand.²

Rolex supplied her with an Oyster for that second attempt, in exchange for a written testimonial. The Times reported: "Hanging round her neck by a riband on this swim, Miss Gleitze carried a small gold watch, which was found this evening to have kept good time throughout."³ The watch survives, a nine carat gold octagonal Oyster, reference 34075, and its case back carries the inscription Miss M. Gleitze The Companion "Oyster". Vindication Channel Swim. October 21st. 1927, which names the second swim and not the crossing. It passed by descent through Gleitze's family and was sold at Christie's in London on 12 June 2000, then held in a private collection for 25 years and sold again at Sotheby's in Geneva on 9 November 2025.⁴

The front page

A month after the vindication swim Rolex bought the front page of the Daily Mail. Secondary accounts date the advertisement to 24 November 1927 and describe Rolex taking the entire page.⁵ English Wikipedia gives a longer version, a front-page advertisement in every issue for a month.⁶ Rolex publishes neither a day nor a duration, only the fact and what it takes from it: "To celebrate the crossing of the channel, Rolex published a full-page ad on the front page of the Daily Mail proclaiming the success of the waterproof watch. This event marked the birth of the Testimonee concept."⁷

On 25 October, four days after the swim, Gleitze wrote to the company that the Oyster "proved itself a reliable and accurate timekeeping companion even though it was subjected to complete immersion for hours in sea water at a temp of not more than 58 and often as low as 51".⁵ No archive consulted reproduces the advertisement's copy, so the letter is the only text from the campaign that can be read today.

Which swim

Rolex's current history page ends one paragraph with two statements. The first: "In 1927 a Rolex Oyster crossed the English Channel, worn by a young English swimmer named Mercedes Gleitze." The second: "The swim lasted over 10 hours and the watch remained in perfect working order at the end of it."⁷ The crossing Gleitze completed took 15 hours and 15 minutes.¹ The inscription on the case back names the swim of 21 October, the one she did not finish.⁴

The word arrived afterwards

Rolex titles its page on her "The first Rolex Testimonee" and dates the birth of the concept to her swim. The term is the company's own, capitalised, and still in service: the page for its tennis partnerships is titled Rolex Testimonees in Tennis and lists 32 testimonees.⁸

Celebrity endorsement predated 1927. Lillie Langtry fronted Pears Soap in 1882, and Wedgwood had used royal endorsement in the eighteenth century.⁹ What Rolex claims is about its own practice: a named category of partner, which it dates to this swim.⁷ The proof the campaign rested on is in Gleitze's letter, which records an immersion, a duration and a water temperature in the swimmer's own words, written four days after she came out of the sea.⁵ Rolex also submerged Oyster models in aquariums displayed in the windows of its main points of sale, where the same demonstration was available to anyone walking past.⁶