Sylvius, Franciscus

orig. Franz de le Boë French François du Bois

born March 15, 1614, Hanau, Ger.

died Nov. 15, 1672, Leiden, Neth.

German-born Dutch physician, physiologist, anatomist, and chemist.

He based his medical system on William Harvey's discovery of the circulation of the blood and believed that the most important life processes, both normal and pathological, took place in the blood. He proposed that chemical imbalances consist of an excess of either acids or alkalies in the blood and devised drugs to counteract them. An outstanding teacher, he had students instructed on hospital wards. He was the first to distinguish glands made up of smaller units with converging ducts from those forming a rounded mass. Several anatomical structures are named after him.

* * *

▪ German physician

also called Franz, or François, De Le Boë, or Du Bois

born March 15, 1614, Hanau, Ger.

died Nov. 15, 1672, Leiden, Neth.

 physician, physiologist, anatomist, and chemist who is considered the founder of the 17th-century iatrochemical school of medicine, which held that all phenomena of life and disease are based on chemical action. His studies helped shift medical emphasis from mystical speculation to a rational application of universal laws of physics and chemistry.

      Basing his medical system on the recent discovery of the circulation of the blood by the English anatomist William Harvey, while keeping it within the general framework of the classic Greek physician Galen's humoral theories, Sylvius felt that the most important processes of normal and pathological life take place in the blood and that diseases (human disease) should be explained and treated chemically. Recognizing the existence of salts in living matter, he concluded that they were the result of an interaction of acids and bases; thus, he postulated that chemical imbalances consist of either an excess of acid (acidosis) or an excess of alkali (alkalosis) in the blood, and he devised drugs to counteract these conditions.

      A professor of medicine at the University of Leiden (1658–72), Sylvius was one of Europe's outstanding teachers. He was among the first to introduce ward instruction in medical education, and he instigated the construction of perhaps the first university chemistry laboratory. He was the first to distinguish between two kinds of glands: conglomerate (made up of a number of smaller units, the excretory ducts of which combine to form ducts of progressively higher order) and conglobate (forming a rounded mass, or clump). He also discovered (1641) the deep cleft (Sylvian fissure) separating the temporal (lower), frontal, and parietal (top rear) lobes of the brain.

* * *