Albrecht Von Haller
1708-1777
Swiss Physiologist and Poet
Albrecht von Haller was the father of modern experimental physiology. By uniting the fields of anatomy and "living anatomy," Haller created a functional approach to studying the physiology of the body. Haller's doctrine concerning the contractility or irritability of muscle tissue laid the foundation for the emerging field of neurology. An illustrious scholar and prolific writer, Haller influenced eighteenth century thought in poetry, botany, philosophy, and medicine.
Born in Bern, Switzerland, Haller was a physically frail but precocious student. He wrote scholarly articles by age eight, and finished a Greek dictionary by age ten. At seventeen, Haller studied medicine at The University of Leiden in the Netherlands under Hermann Boerhaave (1668-1728), the century's greatest medical teacher. After obtaining his medical degree in 1727, Haller continued his studies of anatomy, surgery, and mathematics in London and Paris. During this time, Haller began additional studies in botany after an inspiring trip collecting flora in the Swiss Alps. Haller eventually published a popular volume of poetry including "Die Alpen," a poem which illustrated the beauty of the Swiss Alps, inspired German pride, and influenced German literature.
Haller traveled to the University of Göttingen in 1736 to serve as professor of medicine, anatomy, surgery, and botany, a position he held for 17 years. At Göttingen, Haller performed extensive animal experimentation to improve the principle of general irritability, proposed earlier by English scientist Francis Glisson (1597-1677). Haller showed in 1752 that irritability (contractility) is a property inherent in muscle fibers, while sensibility is an exclusive quality of nerves. By this experimentation, the fundamental division of fibers according to their reactive properties was established. Haller concluded that muscular tissue contracted independently of the nerve tissue around it, and therefore explained why the heartbeats: contraction of muscular tissue stimulated by the influx of blood. Even after the electrophysiology pertaining to the heart was understood more than one hundred years later, Haller's basic suppositions regarding tissue contractility remained essentially correct. Haller's experiments also showed that nerves were inherently unchanged when stimulated, but caused the muscle around it to contract, thus implying that nerves carry impulses which cause sensation. This distinction between nerve and muscle action illustrated by Haller provided the framework for the advent of modern neurology.
Albrecht von Haller. (Library of Congress. Reproduced with permission)Haller's additional contributions to physiology included works on respiration and embryology. Through experimentation, Haller refuted earlier teachings that the lungs contract independently. Haller was the first physician to use a watch to count the pulse. As scientific debate began between preformationists (those who believed that the human was totally preformed in miniature) and epigenesists (those who believed that not all organs were preformed, but appeared during the formation of the fetus), Haller studied developing chick embryos. Although Haller showed that the heart of a developing chick became apparent in the thirty-eighth hour, he sided with the preformationists, impeding the study of embryology for many years.
In 1753, Haller returned to Bern where he practiced medicine and continued his research, publishing extensive scientific works and sustaining a voluminous correspondence with scholars across Europe. Haller presented the knowledge of his time in anatomy and physiology grouped together in his eight-volume Elementa Physiologiae Corporis Humani (Physiological Elements of the Human Body). A milestone in medical history, the series of books is considered the first modern textbook of physiology. In his later years, Haller compiled twenty volumes of bibliographies on medicine, surgery, anatomy, and botany.
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