Afterwards came Captain James Ross, who, in 1818, rounded the coasts of Baffin's Sea, and corrected the hydrographic errors of his predecessors. Lastly, in 1819 and 1820, the celebrated Parry passed through Lancaster Straits, and penetrated, in spite of unnumbered difficulties, as far as Melville Island, and won the prize of 5,000 pounds promised by Act of Parliament to the English sailors who would reach the hundred and seventeenth meridian by a higher latitude than the seventy-seventh parallel. In 1826 Beechey touched Chamisso Island; James Ross wintered from 1829 to 1833 in Prince Regent Straits, and amongst other important works discovered the magnetic pole. During this time Franklin, by an overland route, traversed the septentrional coasts of America from the River Mackenzie to Turnagain Point. Captain Back followed in his steps from 1823 to 1835, and these explorations were completed in 1839 by Messrs. Dease and Simpson and Dr. Rae. Lastly, Sir John Franklin, wishing to discover the North-West passage, left England in 1845 on board the _Erebus_ and the _Terror_; he penetrated into Baffin's Sea, and since his passage across Disko Island no news had been heard of his expedition. That disappearance determined the numerous investigations which have brought about the discovery of the passage, and the survey of these Polar continents, with such indented coast lines. The most daring English, French, and American sailors made voyages towards these terrible countries, and, thanks to their efforts, the maps of that country, so difficult to make, figured in the list of the Royal Geographical Society of London. The curious history of these countries was thus presented to the doctor's imagination as he leaned on the rail, and followed with his eyes the long track left by the brig. Thoughts of the bold navigators weighed upon his mind, and he fancied he could perceive under the frozen arches of the icebergs the pale ghosts of those who were no more. CHAPTER VII DAVIS'S STRAITS