A diving method where a diver uses a regulator as the breathing apparatus and a tank with compressed air which enables the diver to breathe normally underwater

Top half of the kayak.

Crossbars reinforcing the canoe and prevents sides from pulling apart under load.

He developed an improved diving bell.

This aquatic activity involves peeking through life underneath water by swimming with the aid of a snorkel and mask

A piece of equipment that makes it possible to breathe at the surface while the face is the submerged in water.

Like water skiing on a surfboard. 

Surfing very, very big waves.

This is a special valve on top of the tube that completely stops water (and air) from entering the tube when a wave comes or when diving underwater

This type of kayaking is where the kayak is typically fitted with a fin, rather like a surfboard.