WALLER, AUGUSTUS VOLNEY

(b. Faversham, England, 21 December 1816; d. Geneva, Switzerland, 18 September 1870), neurophysiology, neurohistology.

Waller, the son of William Waller, was raised at Nice until his father’s death in 1830. He then returned to England, living with Dr. Lacon Lambe and then with William Lambe, a noted vegetarian. Following early training in the physical sciences, Waller studied medicine at Paris, receiving the M.D. degree in 1840. The following year he became a licentiate of the Society of Apothecaries in London and began a successful general practice in Kensington. In 1842 Waller married Matilda Walls; they had two daughters and one son, the physiologist Augustus D. Waller.

The publication of two papers in the Philosophical Transactions (1849, 1850) led to Waller’s election as a fellow of the Royal Society in 1851. That same year he abandoned his general practice and moved to Bonn in order to devote full time to research; he spent five years there, working principally with the ophthalmologist Julius Budge. The investigations begun in England and continued in Bonn brought Waller the Monthyon Prize of the French Academy of Sciences in 1852 and 1856, and a Royal Society medal in 1860.

After leaving Bonn in 1856 Waller worked in Pierre Flourens’s laboratory at the Jardin des Plantes but developed a chronic fever that invalided him for two years. He returned to England and in 1858 was appointed professor of physiology at Queen’s College, Birmingham, and physician to the college hospital. A heart condition soon forced him to relinquish these posts, and in the same year he retired to Bruges. Ten years later he moved to Geneva, where he hoped to resume general practice. In the spring of 1870 Waller went briefly to London to deliver the Royal Society’s Croonian lecture; he returned to Geneva, where he died suddenly on 18 September.

Waller is best remembered for pioneering a major technique for unraveling the complex structure of the nervous system, the method of secondary of Wallerian degeneration. His interest in the functional anatomy of the nervous system began while he was a medical student in Paris, when he began to study the histology of the frog’s tongue. Like other neurohistologists and physiologists in the first half of the nineteenth century, Waller must have found the processes of nerve degeneration and regeneration to be one of the most difficult problems he confronted in trying to elucidate the structure of the nerve fiber. In retrospect, we know today that the large body of erroneous belief about the fine structure of nerve fibers and nerve cells that arose in the eighteenth and nineteenth centuries resulted in part from mistaking the products of nerve degeneration—the structures seen after a nerve was sectioned or otherwise injured—as normal structures. Our knowledge that the nerve cell body is a trophic center, and that a detached nerve cell process consequently will degenerate and die, began with Waller’s studies of the frog’s tongue.

Using the simple technique of cutting the nerves in the tongue, Waller found in 1849 that degeneration occurred throughout the axon’s distal segment and concluded that the nerve cell body is the axon’s source of nutriment. His belief that the proximal part of the nerve process and the cell body itself did not degenerate following sectioning of the fiber was subsequently modified through the development of improved staining methods. Waller’s study, first reported in the Philosophical Transactions (1840), added to the growing evidence that nerve cell bodies and processes were somehow interconnected. By the 1880’s, when the origin of nerve fibers from nerve cells had been firmly established with the development of better methods for fixing and staining tissues. the Wallerian method became a major means of tracing the origin and course of nerve fibers and tracts; and in the hands of such investigators as Forel, it helped to establish the neuron theory.

Fundamental studies of the autonomic nervous system, conducted during his five years in Bonn, formed the second major area of Waller’s researches. In 1851 and 1852, Budge and Waller published three memoirs in the Comptes rendus of the Paris Academy, examining the role of the nervous system on the motion of the eye’s iris. In a series of well-designed and carefully executed experiments, they showed the influence of the cervical portion of the sympathetic nerve in dilation of the pupil. They then used the Wallerian method to trace the pathway of the pupillary dilator fibers in the dog, following them in the sectioned sympathetic nerve trunk to the first and second thoracic segments of of the spinal cord. When this region was then stimulated in the intact animal, the pupils of the eye dilated. When in turn the cervical part of the sympathetic nerve was sectioned unilaterally, electrical stimulation in the thoracic area no longer caused pupillary dilation on the side that had been sectioned. Budge and Waller termed the area of the sympathetic nerve trunk controlling dilation of the pupils the “ciliospinal center.”

After receiving the Monthyon Prize for the work on the ciliospinal center, Waller went on to demonstrate the action of the cervical sympathetic nerves on the constriction of blood vessels in the head. His experiments on the vasoconstrictor properties of the nerves from the ciliospinal region confirmed and extended the discoveries of Claude Bernard in 1851 and of Brown-Séquard in 1852.

Waller’s work was not confined to the definition of neural structure and function. The readers of Philosophical magazine in the 1840’s, for example, found that Waller had turned his microscope upon a variety of objects: “The Microscopic Observations on the Perforation of the Capillaries by the Corpuscles of the Blood” (November 1846), “Origin of Mucus and Pus” (November 1846), and “Microscopic Investigations on Hail” (July and August 1846, March 1847).

BIBLIOGRAPHY

I. Original Works. Waller’s writings include “Experiments on the Section of the Glossopharyngeal and Hypoglossal Nerves of the Frog, and Observations of the Alterations Produced Thereby in the Structure of Their Primitive Fibres,” in Philosophical Transactions of the Royal Society, 140 (1850), 423–429; “Nouvelle methode pour l’étude du système nerveux, applicable à I’investigation de la distribution anatomique des cordons nerveux, et au diagnostique des maladies du système nerveux, pendant la vie et après la mort,” in Comptes rendus…de I’Académie des science, 33 (1851), 606-611; “Recherches sur le système nerveux. Première partie. Action de la partie cervicale du nerf grand sympathétique et d’une portion de la moelle épinière surla dilatation de la pupille,” ibid., 370–374, written with J. L. Budge; “Recherches expérimentales sur la structures et les fonctions des ganglions,” ibid., 34 (1852), 524–524—also papers by Waller on 582–587, 675–679, 842–847; “Septième mémoire sur le système nerveux,” ibid., 35 (1852), 301 – 306; ’Huitième mémoire…,” ibid., 561 – 564; and “On the Results of the Method Introduced by the Author of Investigating the Nervous System, More Especially as Applied to the Elucidation of the Functions of the Pneumogastric and Sympathetic Nerves,” in Proceedings of the Royal Society, 18 (1869 – 1870), 339 – 343, the Croonian lecture.

II. Secondary Literature. See D. Denny Brown, “Augustus Volney Waller,” in W. Haymaker, ed., Foundersof Neurology (Springfield, III., 1953), 95 – 98; R. Gertler-Samuel, Augustus Volney Waller (1816 – 1870) als Experimentalforscher (Zurich, 1965); and D’Arcy Power, “Waller, Augustus Volney,” in Dictionary of National Biography, XX, 579 – 580.

Judith P. Swazey