Duarte Pacheco Pereira - After India

After India

His diary (1506), preserved in the Portuguese National Archive (Torre do Tombo), is probably the first European document to acknowledge that chimpanzees built their own rudimentary tools.

Between 1505 and 1508 Duarte Pacheco Pereira composed a book, Esmeraldo de situ orbis, inspired on Pomponius Mela's De situ Orbis, which has been described as one of the first major scientific works "reporting on what was observed and experimented in the newly 'discovered' environment." Never completed, it was not published until 1892, possibly to avoid giving others information about Portugal's valuable Guinea trade.

(The meaning of the 'esmeraldo' in the title has been much speculated. Among the proposals, it is a reference to the emerald green of the sea; that it is an anagram combining the names 'Emmanuel' (for King Manuel I of Portugal) and 'Eduardus' (of Duarte Pacheco), that Esmeralda might have been the name (or nickname) of the ship Duarte Pacheco sailed to India, that it is a corruption of the Spanish word esmerado (meaning "guide"), that in Malayalam, an emerald gemstone is known as pache or pachec, and thus Esmeraldo is a pun on his own name (thus, "Pacheco's De Situ Orbis").

In 1508, Duarte Pacheco was commissioned by the Portuguese king to give chase to Mondragon French privateer which operated between the Azores and the Portuguese coast, where they attacked the ships coming from Portuguese India. Duarte Pacheco located and cornered Mondragon off Cape Finisterre in 1509, and defeated and captured him.

Later in life, while away governing São Jorge da Mina, he was slandered by his enemies at court with accusations of theft and corruption. He was recalled to the capital and briefly imprisoned until he was exonerated by the Crown being proved innocent. But the damage was done as he had lost his governorship, his wealth, and influence. Although he was acquitted his protector, King João II of Portugal had died and been replaced by a king who didn't acknowledge the value of Duarte Pacheco. Duarte Pacheco had served the previous king as a squire, and had served King Manuel merely as a high ranking servant. His distance from Lisbon and his success meant he had many enemies abroad, and few friends in the capital to defend him. He died alone and penniless.

According to one of its most important biographers, the Portuguese historian Joaquim Barradas de Carvalho, who lived in exile in Brazil in the 1960s, Duarte Pacheco was a genius comparable to Leonardo da Vinci. With the anticipation of more than two centuries, the cosmographer was responsible for calculating the value of the degree of the meridian arc with a margin of error of only 4%.