Dutch physician and botanist who co-authored one of the earliest works on the natural history of Brazil, with Georg Marcgrave. Willem Piso was born in Leiden, where his father was a church organist. He studied medicine at the University of Leiden and then in Caen, France, graduating in 1633 and going on to practise medicine in Amsterdam.
In 1637 he was appointed personal physician to Count Johan Maurits van Nassau-Siegen by the Dutch West India Company. The Netherlands had taken control of the north-east corner of Brazil in 1624 and the count had been appointed governor of the colony at Recife, Pernambuco. He was a scientifically minded man and decided that while he defended the territory against Portuguese forces, the land should also be explored in terms of resources and natural history. Piso was to be part of this exploration, and was sent for along with two German students of mathematics and medicine, Georg Marcgrave and H. Cralitz. The young Cralitz died within a year of his arrival in Brazil in 1637, but Piso and Marcgrave lived out more than six years in the country, both practising medicine and serving as surgeons to the Dutch troops as well as investigating the natural riches of the region. Piso's interest was chiefly in medicinal plants and thus he later completed four books on the subject (De medicina Brasiliense) for Historia Naturalis Brasiliae (1648), a further eight on the country's botany and zoology being produced by Marcgrave. The work of the latter was edited by Johannes de Laet (1593-1649) of the Dutch West India Company as Marcgrave died in Angola in 1640, before the work was compiled.
On his return to the Netherlands in 1640 Piso lived in Leiden and then Amsterdam once more, where he mixed in the scientific community for many years. He was appointed Inspector of the Amsterdam Medical College in 1655, rising afterwards to Dean. Conducting a successful medical practice and completing a second edition of the Historia Naturalis under his own name, he amassed a large personal fortune. The revision of the original work, De Indiae Utrusque re naturali et medica (1658), condensed into eight books, was however criticised from many corners for its careless treatment of the work of Marcgrave, who had deliberately written his work on botany and zoology in a code to hamper Piso should he attempt to take credit for it in the German's absence. The suspicions of Marcgrave, who had uncanny foresight in this case, have been deduced due to the fact that he did not encode his astronomical or mathematical work written in Brazil, Piso knowing little of these subjects. Despite the questionable relationship of the collaborators and Piso's dubious handling of his co-author's work, Piso is recognised as one of the earliest authorities on tropical medicine. Among the diseases that he described are American trypanosomiasis, treponematoses (yaws), various types of dysentery and problems arising from dietary insufficiencies. He also noted native remedies and noticed, for example, that native populations did not suffer from night blindness like the Dutch soldiers. He attributed this to their different diets, that of the colonists lacking in fresh fish and vegetables.
Sources:
C.R. Boxer, 1973, The Dutch in Brazil 1624-1654: 112-158
R.F. Erickson, "Willem Piso", MBG Rare Books:
http://www.illustratedgarden.org/mobot/rarebooks/author.asp?creator=Piso,%20Willem&creatorID=111
E.W. Gudger, 1912, "Georg Marcgrave, the first student of American Natural History", The Popular Science Monthly, 81: 250-274
E. Pies, 1981, Willem Piso (1611-1678): Begründer der Kolonialen Medizin und Leibarzt des Grafen Johann Moritz von Nassau-Siegen in Brasilien
A.R. Steele, 1964, Flowers for the King: 14.
