Advertências de Navegantes, authored by Marcos Cerveira de Aguilar, is a codex dated to 1640 and presently located in the Biblioteca Nacional in Lisbon. On folio two its author mentions "the 1st of December of this year of 1640," which is the date of the rebellion that made Portugal independent from the Spanish crown. It is a rather complete overview of the Portuguese navy, from the construction of ships, rigging and fitting, launching, and manning to a collection of chapters with general rules and knowledge useful to every navy officer.