It was discovered by Captain Fernandez Duro, the well-known historian of the Spanish navy, amongst the manuscripts in the library of the Academy of History at Madrid.

The exact date of its production is not known; but Alonso de Chaves was one of a group of naval writers and experts who flourished at the court of the Emperor Charles V in the first half of the sixteenth century.[1] He was known to Hakluyt, who mentions him in connection with his own cherished idea of getting a lectureship in navigation established in London.

'And that it may appear,' he writes in dedicating the second edition of his _Voyages_ to the lord admiral, 'that this is no vain fancy nor device of mine it may please your lordship to understand that the late Emperor Charles the Fifth ...

established not only a Pilot-Major for the examination of such as sought to take charge of ships in that voyage' (_i.e._ to the Indies), 'but also founded a notable lecture of the Art of Navigation which is read to this day in the Contractation House at Seville.

The Readers of the Lecture have not only carefully taught and instructed the Spanish mariners by word of mouth, but also have published sundry exact and worthy treatises concerning marine causes for the direction and encouragement of posterity.