In 1924, the company R.W.C now named Rolex,launched the first trademarked "Submarine",a water resistant wristwatch.As we all should no The biggest enemy of any watch is water.And without proper seals etc
even on a warm day the crystal could mist up on wrist when worn.Now
old Hans Wilsdorf was a clever man,and wanted to increase sales worldwide and especially in tropical climates.So he tried to make a watch that was waterproof.Now the evolution of the oyster case was started,his idea was very simple.He would fit a case inside a case,and called it the Submarine.Now this worked,but had certain drawbacks you had to open the case to wind it.And the outer case had a threaded screw on bezel to protect the watch.This was not user owner friendly and caused wear on the hinges and bezel threads.So he started to look for a new idea for a waterproof wrist watch.So later in 1925 he heard that two watchmakers one was Paul Perregaux.Had taken out a swiss patent for a twin lock screwed stem system crown.Now Hans Wilsdorf of Rolex grasped that a hermetically sealed case, together with careful fitting of the crystal and a special stem mechanism, would produce a better water proof wristwatch.He quickly negotiated to have the Perregaux patent assigned to him. Wilsdorf then obtained a British patent on October 18 1926.And then soon after the Rolex Oyster was born and became a commercial success.. In 1927, a stenographer, Mercedes Gleitze, swam the English Channel with the unheard of accompaniment of a wristwatch –the Rolex Oyster— on her wrist for the entire 15 hour, 15 minute,swim and the rest is Rolex history,and had to wait 30 odd years for the rebirth,from Submarine, to Submariner..
First Rolex Submarine.

Paul Perregaux patent screwed stem system 1925,which Hans Wilsdorf of Rolex acquired,to make the first oyster cased Rolex.
even on a warm day the crystal could mist up on wrist when worn.Now
old Hans Wilsdorf was a clever man,and wanted to increase sales worldwide and especially in tropical climates.So he tried to make a watch that was waterproof.Now the evolution of the oyster case was started,his idea was very simple.He would fit a case inside a case,and called it the Submarine.Now this worked,but had certain drawbacks you had to open the case to wind it.And the outer case had a threaded screw on bezel to protect the watch.This was not user owner friendly and caused wear on the hinges and bezel threads.So he started to look for a new idea for a waterproof wrist watch.So later in 1925 he heard that two watchmakers one was Paul Perregaux.Had taken out a swiss patent for a twin lock screwed stem system crown.Now Hans Wilsdorf of Rolex grasped that a hermetically sealed case, together with careful fitting of the crystal and a special stem mechanism, would produce a better water proof wristwatch.He quickly negotiated to have the Perregaux patent assigned to him. Wilsdorf then obtained a British patent on October 18 1926.And then soon after the Rolex Oyster was born and became a commercial success.. In 1927, a stenographer, Mercedes Gleitze, swam the English Channel with the unheard of accompaniment of a wristwatch –the Rolex Oyster— on her wrist for the entire 15 hour, 15 minute,swim and the rest is Rolex history,and had to wait 30 odd years for the rebirth,from Submarine, to Submariner..
First Rolex Submarine.

Paul Perregaux patent screwed stem system 1925,which Hans Wilsdorf of Rolex acquired,to make the first oyster cased Rolex.

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