Robert Whytt

Robert Whytt (1714–1766) was a Scottish physician. His work, on unconscious reflexes, tubercular meningitis, urinary bladder stones, and hysteria, is remembered now most for his book on diseases of the nervous system. He served as President of the Royal College of Physicians of Edinburgh.

The second son of Robert Whytt of Bennochy (near Kirkcaldy in Fife), advocate, and Jean, daughter of Antony Murray of Woodend, Perthshire, he was born in Edinburgh on 6 September 1714, six months after his father's death. Having graduated M. A. at the University of St Andrews in 1730, he went to Edinburgh to study medicine. Two years before this he had succeeded, on the death of his elder brother George, to the family estate. Whytt devoted himself to the study of anatomy, under the first Monro. Going to London in 1734, Whytt became a pupil of William Cheselden, while he visited the wards of the London hospitals. After this he attended the lectures of Jacob B. Winslow in Paris, of Herman Boerhaave and Bernhard Siegfried Albinus at Leyden. He took the degree of M. D. at Reims on 2 April 1736. On 3 June 1737, a similar degree was conferred on him by the University of St Andrews, and on 21 June he became a licentiate of the Royal College of Physicians of Edinburgh. On 27 November 1738, he was elected to the fellowship, and began practice as a physician.

Whytt's theories on the nervous system and its role in movement opposed many of the teachings that were in place in the 18th century. During that time, many physiologists still supported Descartes' theory of movement which hypothesized that muscle contraction was due to the activation of fluid in the nervous system called animal spirits. Furthermore, he rejected Haller's theory by claiming that movement must depend on interconnecting nerves that lead to the brain or spinal cord. In Whytt's version of the experiment, he inserted a hot wire through the spine of the decapitated frog and observed that when the spine of the frog was destroyed, no form of pricking or cutting of the frog's limb elicited a response. If the frog's spine stayed intact as it did in Hales' experiment, the limbs continued to respond to the pricking and cutting. In 1745, Whytt published An Equiry Into the Cause Which Promote the Circulation of Fluids in the Small Vessels of Animals where he states that the soul, also referred to as the sentient principle, and the body hold equal influence over movement and therefore may govern both voluntary and involuntary action. Whytt discovers the pupillary light reflex based on an autopsy of a child suffering from hydrocephalus whose pupils were noted to be unresponsive to changes in light. and was translated into German by Christian Ehrhardt Kapp in 1771 (Leipzig). A complete list of his papers is in Robert Watt's Bibliotheca Britannica.

He was twice married. His first wife, Helen, sister of James Robertson, governor of New York, died in 1741, leaving no children. In 1743 he married Louisa, daughter of James Balfour of Pilrig in Midlothian, who died in 1764. By his second wife Whytt had six surviving children. His grandson Lewis Balfour was the grandfather of Robert Louis Stevenson. Whytt's son John, who changed his name to Whyte, became heir to the entailed estates of General Melville of Strathkinness, and took the name of Melville in addition to his own. He was grandfather of Captain George John Whyte Melville.