Note 383 — Chapter I · (continued 2)
Reading edition
Cf. Lelewel, Géographie du moyen-âge, ii. 160. The rules of Gemma Frisius for discovering longitude were given in Eden’s Peter Martyr (1555), folio 360. An earlier book was Francisco Falero’s Regimiento para observar in longitud en la mar, 1535. Cf. E. F. de Navarrete’s “El problema de la longitud en la mar,” in volume 21 of the Doc. inéditos (España); and Vasco da Gama (Hakluyt Soc.), pp. 19, 25, 33, 43, 63, 138.