It has also been surmised, without any certain evidence,[231] that D. Pedro presented his brother with various maps of Gabriel Valsecca,[232] and with the writings of Georg Purbach, the instructor of Regiomontanus. Much more certain and interesting is the allusion to the Infant's collection of old maps in the history of the discovery of St. Michael (1443-4) in the Azores. A runaway slave, having escaped to the highest peak in the Isle of St. Maria, sighted a distant land, and returned to his master to gain pardon with this news. Prince Henry was informed of this, consulted his ancient charts, and found them confirm the slave's discovery. So he sent out Gonçalo Velho Cabral to seek for the same. Cabral failed; but on his returning to the Prince, the latter showed him from the ancient maps how he had only missed it by a slight error of direction. On his second trial the explorer was successful, and reached St. Michael on May 8, 1444. [Footnote 231: But see Gaspar Fructuoso, _Saudades da terra_ (ed. Azevedo, 1873), bk. ii, p. 9; Cordeiro, _Historia Insulana_, ii, p. 2; Santos, _Memoria sobre dois antigos mappas, etc._, in _Mem. de Litt. da Academia_, viii, pp. 275-301; O. Martins, _Os Filhos de D. João I_, p. 72.] [Footnote 232: One of which (A.D. 1434-1439) is our authority for the earliest known Portuguese voyage to any part of the Azores; viz., that of Diego de Sevill in 1427 (a date hypothetically converted by Major into 1432). This map of Valsecca's only gives St. Mary and the Formigas as known in 1439; see pp. cxxxi, cxxxiv of this Introduction.] * * * * *