About this period the progress of discovery was arrested by political disputes in Portugal, which ended in a civil war between Don Pedro, Duke of Coimbra, and King Alphonso V. his nephew and son-in-law, in the course of which Don Pedro was slain. Don Henry appears to have taken no share in these disputes, except by endeavouring to mediate between his nephew and brother; and, after the unhappy catastrophe of Don Pedro, Don Henry returned to Sagres, where he resumed the superintendence of his maritime discoveries. [1] Explained by the celebrated Dr Johnson, as "so named from its progression into the ocean, and the circuit by which it must be doubled." Introduct. to the World Displayed.--Clarke. [2] Cape Bojador is imagined to have been the _Canarea_ of Ptolemy.-- Clarke I. 15 [3] The _barcha_ is a sort of brig with topsails, having all its yards on one long pole without sliding masts, as still used by tartans and settees. The _barcha longa_ is a kind of small galley, with one mast and oars.--Clarke, I. p. 153. [4] Clarke says in the same year 1418. But this could not well be, as the Discovery of Puerto Santo was made so late as the 1st of November of that year. The truth is, that only very general accounts of these early voyages remain in the Portuguese historians.--E. [5] Such is the simple and probable account of the discovery of Madeira in Purchas. Clarke has chosen to embellish it with a variety of very extraordinary circumstances, which being utterly unworthy of credit, we do not think necessary to be inserted in this place. See Progress of Maritime Discovery, I. 157.--E. [6] In the Introduction to the World Displayed, Dr Johnson remarks on this story, that "green wood is not very apt to burn; and the heavy rains which fall in these countries must surely have extinguished the conflagration were it ever so violent." Yet in 1800 Radnor forest presented a conflagration of nearly twenty miles circumference, which continued to spread for a considerable time, in spite of every effort to arrest its progress.--E. [7] De Barros; Lafitan; Vincent, in the Periplus of the Erythrean sea; Meikle, in his translation of the Lusiad. Harris, in his Collection, Vol. I. p. 663, postpones this discovery to the year 1439.--Clarke. [8] In Purchas this person is named Antonio Gonsalvo; but the authority of Clarke, I. 188, is here preferred.--E. [9] Progr. of Nav. Disc. I. 184. [10] This tribe of Assenhaji, or Azanaghi, are the Zenhaga of our maps, and the Sanhagae of Edrisi and Abulfeda. They are at present represented as inhabiting at no great distance from the coast of Africa, between the rivers Nun and Senegal.--Cl.