|Over the following years, a
Governor-General, Rio de Samo, was brought in to supervise expansion. Not only did Brazil
become the world's largest sugar producer under him, but many Brazilians and Amazonians
suffered as they were forced into labor, slavery, and Jesuit missions. Jesuits attempted
to protect the natives from slavery, and in 1655 Father Antonio Vieira got a royal decree
to halt enslavement by settlers. However, the Jesuits were expelled in 1759.
In 1743, Charles de La Condamine returned from a visit to the Amazon with the first
recorded scientific data on the river, the plants, and the people. He also mapped the
Amazon with remarkable accuracy,investigated the poison used by the Amazonians, and
collected a milky sap would later become latex. Alexander Humboldt followed in 1800 with
the first tests of the electric eel after he had stepped on one. Soon after, the
Amazon was deluged with scientists from all over the world.