The West India Company was able to induce an admirable Governor to take charge of the new possession, Prince John Maurice of Nassau; he reached Recife in 1637, and inaugurated a conciliatory policy towards such Pernambucanos as would accept Dutch rule: those who would not were pursued into the interior forests where they retreated under one of the Albuquerques, and were forced to flee from Alagôas into Bahia. When such resisters were caught they were shipped to Dutch settlements in the East Indies. Religious freedom was promulgated by the Protestant rulers, more systematic administration of settlements and estates inaugurated, better sugar milling methods introduced as well as farming implements, and the scientific exploration of the interior was made. Prince Maurice brought with him map-makers, geologists, botanists and expert mineralogists, and sent them to the valleys and hills of the Bahian hinterlands. Elias Herkmann took an expedition of one hundred men from Recife in 1641, to make scientific investigations, and although he did not find mines of importance he studied native relics and language, subsequently publishing a book on the Tapuyo race. George Marcgraf and Wilhelm Piso are also Dutch names of note in connection with Brazil; the former studied Brazilian topography and water systems and wrote a treatise on the subject as well as the _Historia Rerum Naturalium Brazilium_; the latter was the first classifier of Brazilian flora and fauna. “We owe to him,” says Dr. Egas Moniz of Bahia, “the discovery of the emetic-cathartic properties of ipecacuanha and copaiba” as well as the therapeutic virtues of jaborandi and red mangue and several other drugs obtained from the Brazilian _matto_. The first scientific charting of the sertão behind Pernambuco, Alagôas and north Bahia was done during this time; herds of cattle already wandered over interior pastures, and settlers led by the independent spirit which renders the Brazilian indifferent to solitude had formed fazendas along river borders; explorers had wandered by these water paths looking for mines, but systematic maps and charts were lacking.