However, using the manufactures trade name on the dial of a watch was going against the accepted practice of the time. Historically it was the importers name and not the manufactures that was displayed on the watch dial. It was to take time, money and a major technical innovation to break this tradition. Initially Rolex were successful in having 1 watch in every 6 carrying their trade name, but by 1925 this had only increased to 3 in 6. Therefore tiring of the slow progress, Mr Wilsdorf took an enlightened step.

He spent £12,000 a year, a huge amount for that time, to publicise the Rolex name and heighten public awareness of the brand. This action helped to increase the watches supplied with the Rolex trade name to 5 in 6.

Yet it was not until the invention of the ’Oyster’ case that Rolex could dictate to the importers that every watch supplied by them was to carry the Rolex name. For many years Mr Wilsdorf and his assistants had been working to produce,

‘a watch case so tight that our movements will be permanently guaranteed against damage caused by dust, perspiration, water, heat and cold. Only then will the perfect accuracy of the Rolex be secured’

Finally, in 1926, this objective was achieved with the now patented ‘Oyster’ case, so known, as it was as impenetrable as an oyster! Although this invention was initially thought of with scepticism and took some notable events to break this thought, it is now a standard to which nearly all sports watches are measured.

The last major innovation that was to create the basis for the Sports watch that we know this day took place 5 years later, in 1931. Up to this date, watches required winding by the wearer to give them the energy needed to function. The aim was to do away with this dependence and seek a system that would require no intervention by the wearer.

The idea was not a new one, but it was Rolex that finally perfected and patented the Perpetual self winding mechanism. It operates by a semicircular rotor weight that pivots around its axis and winds the watch at the slightest movement of the wrist.

Now the scene was set. Rolex were now producing a watch small enough to be worn on the wrist, impervious to outside elements and required no winding from the wearer; the Rolex Oyster Perpetual.

The picture shows the patented Rolex vacuum device, ref# 1000, used to test the waterproofness of an ‘Oyster’ case. The watch is immersed in the water and by expelling air a vacuum is created. If there are any leaks in the case, small air bubbles will be seen escaping and rising to the surface.