History of submarines few years before the US, and paralleled subsequent US development in this area. In the 1950s, nuclear power partially replaced diesel-electric propulsion. The sailing of the first nuclear-powered submarine, the USN ""Nautilus"" in 1955 was soon followed by similar British, French and Russian boats. Equipment was also developed to extract oxygen from sea water. These two innovations, together with inertial navigation systems, gave submarines the ability to remain submerged for weeks or months, and enabled previously impossible voyages such as the crossing of the North Pole beneath the Arctic ice cap by the USS "Nautilus" in 1958. Most of the
Penny Ice Cap Captain William Penny, a whaling captain from Aberdeen in Scotland who pioneered over-wintering with native Inuit at Cumberland Sound in order to be able to start whaling (in the nineteenth century) much earlier in the season. He was also engaged by Lady Franklin to search for her husband John, lost with all souls in the search for the North West Passage. Penny Ice Cap The Penny Ice Cap is a ice cap in Auyuittuq National Park of Baffin Island, Nunavut, Canada. It forms a high barrier on the Cumberland Peninsula, an area of deep fiords and glaciated valleys. It is