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
Barnes Ice Cap of the ice cap. Barnes Ice Cap The Barnes Ice Cap is an ice cap located in central Baffin Island, Nunavut, Canada. It covers close to in the area of the Baffin Mountains. It has been thinning due to regional warming. Between 2004 and 2006, the ice cap was thinning at a rate of per year. The ice cap contains Canada's oldest ice, some of it being over 20,000 years old. It is a remnant of the Laurentide ice sheet, which covered much of Canada during the last glacial period of the Earth's current ice age. Generator Lake is located