About this period, or perhaps considerably earlier, Don Henry obtained a bull from Pope Martin V. by which the sovereign pontiff made a perpetual donation to the crown of Portugal, of all lands and islands which had been or might be discovered between Cape Bojador and the East Indies, inclusively, and granted a plenary indulgence for the souls of all who might perish in the prosecution of the enterprize, and in achieving the conquest of these extensive regions from the infidel and pagan enemies of Christ and the church. In this measure, the philosophical genius and enlarged political views of Don Henry are plainly evinced; and, undismayed by the obstacles which had so long opposed his grand project of discoveries, and the length of time which had been employed in making so very small progress, he shewed himself to have looked steadily forwards to the full accomplishment of his hopes of discovering the route by sea from Europe to India, around the still unknown shores of Southern Africa. The date of this papal grant does not certainly appear. De Barros and Lafitau are of opinion that it must have been posterior to 1440; Purchas places it in 1441; and de Guyon in 1444. But Martin V. died in 1431; and these writers seem to have confounded the original grant from that pontiff, with subsequent confirmations by his successors Eugenius IV. Nicholas V. and Sextus IV[9]. The gradual progress of these discoveries were interrupted for a time by an unsuccessful attempt of Edward I. or _Duarte_, king of Portugal, to gain possession of Tangier in the kingdom of Fez. But the history of this war, in which the Portuguese arms suffered much misfortune and dishonour, are quite irrelevant to the present subject. The plague likewise, which raged at Lisbon in 1438, contributed to the suspension of the patriotic enterprizes of Don Henry. At length, in 1440, Don Henry resumed his project of maritime discovery, and dispatched two caravels from Sagres, which were forced back by unfavourable weather, apparently without even reaching the coast of Africa.