Piso, Willem,
(1611 - 1678)

Willem Piso was born in Leiden, the son of Hermann Pies, a church organist, and Cornelia van Liesvelt. He studied first at Leiden University and then moved to Caen in France. Piso graduated from the medical school there in 1633, and returned that year to the Netherlands to practice medicine in Amsterdam. Four years later, the Dutch West India Company offered him the position of personal physician to Count Johan Maurits van Nassau-Siegen (1604-1679) who was at that time in South America in the capacity of Governor of the colony of Dutch Brazil.

The Dutch colony in Brazil existed for thirty years (1624-1654) and by far its most prosperous period was during the tenure of Count Johan Maurits from 1636 to 1644. This eminent nobleman of the House of Orange was an extraordinarily able administrator who governed the colony with skill, wisdom, and tolerance, especially toward the non-Dutch population and to people of other religions. Among his many activities, the promotion of scientific studies had a high priority, and for this, he acquired the services of a number of scientists and artists who mapped out and portrayed Brazil. Willem Piso was one of these.

Piso arrived in Brazil early in 1638 and may have been on the same ship with other scientists, namely the astronomer, Georg Markgraf (1610-1644). Both men accompanied the Count on his military campaigns against the Portuguese in Brazil and were part of his inner circle until he returned to the Netherlands in 1644. Piso went with him, but Markgraf was sent to Angola by the West India Company and died there shortly after his arrival.

In Brazil, Piso maintained a medical practice in Recife and was able to engage in a multitude of scientific and medical investigations. Markgraf was his principal collaborator and their work was published in Historia Naturalis Brasiliae in 1648. After his return to the Netherlands, Piso settled first in Leiden, and then moved to Amsterdam where he became an important member of the Dutch scientific community. In 1655 he was appointed Inspector of the Amsterdam Medical College and later became its Dean. He published a second book on his Brazilian investigations, conducted a highly successful medical practice, amassed a large personal fortune, and after his death, he was buried next to Rembrandt in Amsterdam’s Westerkerk.

The contributions of Willem Piso to Historia Naturalis Brasiliae are in the four books entitled De medicina Brasiliense. These books include many descriptions of diseases and native remedies for them, and establish the author as one of the earliest authorities on tropical medicine. Among the diseases for which he provides a thorough analysis are American trypanosomiasis, treponematoses (yaws), and tungiasis. Piso also studied the causes of dysentery, and the physical problems resulting from dietary deficiencies. One of his significant discoveries was directly related to the high incidence of diseases of the eyes among the Dutch soldiers and civilians in the colony. A number of them suffered from both night and day blindness and other infectious and degenerative conditions. Piso found that the native population did not have many of these problems; especially absent was the condition of night blindness, and he attributed this to a significant difference in diet between the two populations. The native diet was based on fresh fish and vegetables, items which were often lacking in ordinary Dutch eating habits. In another dietary subject, Piso was an early advocate of eating oranges and lemons for the prevention of scurvy, and wrote that Brazilian lemons were outstanding for overcoming that disease.

Georg Markgraf, the co-author of Historia Naturalis Brasiliae, contributed its eight books on botany and zoology. Unlike Willem Piso, whose lifespan was twice as long, his biography is not extensive. He was born in Liebstadt, a small town south of Dresden in Saxony. His father was from an old Liebstadt family, and was the head of the local school. Georg studied botany, astronomy, mathematics, and medicine at various universities in Germany and Switzerland until 1636 when he journeyed to Leiden in the Netherlands. In 1637, he was appointed astronomer of the company which was being formed to sail to the colony in Brazil, and he arrived there in early 1638.

The accounts of the time Markgraf spent in Brazil are sketchy, but it is known that he had an observatory in Recife and that he also practiced medicine. He made a number of expeditions into various parts of the Dutch colony in order to study its natural history and geography and to assemble data for a map of Brazil. The result of his cartographic work was the large map published in 1647 by Caspar Barlaeus (1584-1648). In addition to his accomplishments in astronomy and cartography, Markgraf is singularly important for the contributions he made in zoology and botany. The eight books of Historia Naturalis Brasiliae with the sub- title of Historia rerum naturalium Brasiliae include three on plants and the others on fish,birds, quadrupeds and snakes, and insects, with the eighth book summing up Brazilian geography, ethnology, and meteorology. The arrangement of the work as published was based on Markgraf’s notes edited by Johannes de Laet (1593-1649). The notes, as well as botanical and zoological specimens, were entrusted to Count Johan Maurits when Markgraf departed for Angola, and the former should be regarded as the principal sponsor of the work.

The relationship between the two authors of the great work on Brazil has been a subject of considerable study, primarily because, in 1658, Willem Piso published, under his own name, a second edition of the Historia. Its title was De Indiae Utriusque re naturali et medica, and the author’s treatment of Markgraf’s writings was careless and inaccurate. Linnaeus severely criticized the work, while others, including Markgraf’s brother, accused Piso of having sought to diminish Georg Markgraf’s reputation, even referring to him as “his servant” and accusing him of drunkenness and financial irregularities in Brazil. Based on the first edition of Historia, it appears that the contributions to science of both men were remarkable, but that Markgraf’s were much more comprehensive and established him as one of the most important of the early natural historians of Brazil.

Bibliography.

Irene Perbal Bastin, Brasil – Holandês. 1995
E. van den Boogaart, ed., Johan Maurits van Nassau-Siegen. 1604-1679. 1979.
C. R. Boxer, The Dutch in Brazil 1624-1654, 1973.
L. Darmstaedter, “Georg Marcgrave und Wilhelm Piso, die ersten Erforscher brasiliens”, Velhagen Klasings Monatshefte. 1928. pp. 649-654.
C. F. P. Martius, “Versuch eines Commentars über die Pflanzen in den Werken von Marcgrav und Piso über Brasilien”. Abh. bayer. Acad. Wiss., 7:181-238. 1853.
P. J. P. Whitehead, “The biography of Georg Marcgraf (1610-1643/4) by his brother Christian, translated by James Petiver”, J. Soc. Biblphy nat. Hist., 9:301-314. 1979.
“The original drawings for the Historia naturalis Brasiliae of Piso and Marcgrave (1648)”, ibid., 7:409-422. 1976.

Robert F. Erickson