In 1850, the Admiralty sent Commander Robert McClure aboard the Investigator and Richard Collinson aboard the Enterprise to search for the lost Franklin expedition via the Bering Strait. After the two ships were separated at their first meeting point in Honolulu, McClure and the Invesitgator continued alone travelling northeast and became the first to navigate the Beaufort Sea. He continued past the southern coast of Banks Island and discovered Prince of Wales Strait, where his ship became trapped in the ice part way up the strait. He continued up the strait by sledge where it led to Viscount Melville Sound, shown on this map. Since a route through the sound to Baffin Island was established, McClure decided that he discovered the Northwest Passage (however, this route was discovered by the Franklin expedition four years earlier). Eventually, McClure had to abandon his ship in the ice and return to Great Britain, where he and his men were awarded £10,000 for their discovery of the Northwest Passage.
From April to July 1853, George Frederick Mecham, under the command of the Admiralty’s Captain Sir Edward Belcher, made one of the longest sledge journeys in the Arctic at that time. Mecham and his party travelled west across Melville Island to Cape Russell, continued to Eglinton Island and then traversed the southern and western coasts of Prince Patrick Island before returning back along the north coast of Eglinton Island to the ships — a total distance of about 1,800 kilometres and charting about 1,000 kilometres of shoreline. This map depicts his epic journey and is the first to chart Eglinton and Prince Patrick islands.