Joao Baptista Lavanha is said to have studied in Rome. He was appointed by Philip II of Spain to be professor of mathematics in Madrid in 1582.
Philip had sent the Duke of Alba with an army to conquer Portugal in 1580 and soon realised that Portugal was more advanced in studies of navigation than Spain. In an attempt to correct this, Philip founded an Academy of Mathematics in Madrid with Lavanha as its first professor.
From 1587 Lavanha became chief engineer to Philip II. He was appointed cosmographer to the king in 1596 and about the same time he moved to Lisbon where he taught mathematics to sailors and navigators.
Lavanha is best known for his contributions to navigation. His book Regimento nautico gives rules for determining latitude and tables of declination of the Sun.
He also worked on maps, producing some interesting new ideas. He produced a map of Aragon in about 1615.
Among his publications was a translation of Euclid.
Lavanha also studied instruments used in navigation, constructing astrolabes, quadrants and compasses. He also devised a new navigational instrument.
Article by: J J O'Connor and E F Robertson