Cornelis Jacobszoon Drebbel (1572 – 7 November 1633) was a Dutch engineer and inventor. He was the builder of the first navigable submarine in 1620 and an innovator who contributed to the development of measurement and control systems, optics and chemistry.
Cornelis Drebbel was born in Alkmaar, Holland in an Anabaptist family in 1572. After some years at the Latin school in Alkmaar, around 1587, he attended the Academy in Haarlem, also located in North-Holland.
He also built the first navigable submarine in 1620 while working for the English Royal Navy. He manufactured a steerable submarine with a leather-covered wooden frame. Between 1620 and 1624 Drebbel successfully built and tested two more submarines, each one bigger than the last. The final (third) model had 6 oars and could carry 16 passengers. This model was demonstrated to King James I in person and several thousand Londoners.
The submarine stayed submerged for three hours and could travel from Westminster to Greenwich and back, cruising at a depth between 12 and 15 feet (4 to 5 metres). Drebbel even took King James in this submarine on a test dive beneath the Thames, making King James I the first monarch to travel underwater.
This submarine was tested many times in the Thames, but it couldn't attract enough enthusiasm from the Admiralty and was never used in combat.
More recently it has been suggested that the contemporary accounts of the craft contained significant elements of exaggeration and it was at most a semi-submersible which was able to travel down the Thames by the force of the current. However, semi- and even completely submerged ships as well as fully covered ships were no novelty at all back then and had been used in action several times, each time attracting headlines.
According to en.wikipedia