The double eponym is a recent invader of medical literature because of the individual nature of medical discovery before the early years of the 19th century. The titans of medicine—Hippocrates, Galen, Vesalius, Harvey, Morgagni, Sydenham, Heberden, Corvisart, Laënnec, and Trousseau, to name but a few—were solo investigators and writers. Even William and John Hunter did not collaborate, except that William was assisted in a minor way by his brother in the delineation of the maternal and fetal circulations. In fact, years later John picked a public quarrel with his older brother over a quibble about priority. Although the medical giants developed schools and surrounded themselves with students and assistants, they were scientifically many heads taller than their auditors.
Evidence of medical collaboration appeared first in the persons of the three Weber brothers of Wittenberg. In 1825, Ernst Heinrich Weber, professor of anatomy and physiology at Leipsig, with his middle brother,