nautilus submersible by sergey akulenok from russia

The construction of submersibles is based on the biological entity known as “Nautilus”, one of the ancient cephalopod mollusks found in warm seas. Submersibles allow a person to dive and remain underwater for periods exceeding the natural capacity of the human lung. Other diving systems exist, such as SCUBA gear (including rebreathers) require special training and impose limits on the depth and duration of the dive. However, with a submarine, anyone can see the wonderful world of reefs, coral and other life, and the sea floor. Diving can be arranged and supervised with an instructor. The controls of the submarine are often situated in the center, and are accessible by both occupants. The occupants can easily communicate, which is a very valuable feature, especially in an educational setting. Often, submersibles use direct-drive electric motors but other drives exist, including nuclear, diesel, and the original hand-powered and steam powered variants.