(b. Bologna, Italy, 1543; d. Rome, Italy, 1575)
Varolio, the son of Sebastiano Varolio, a Bolognese citizen, studied medicine at the University of Bologna. He displayed interest and aptitude in particular for anatomy, which he pursued under the direction of Giulio Cesare Aranzio. Varolio received his medical degree in 1567, and in 1569 was given the extraordinary chair of surgery, which carried with it the responsibility of teaching anatomy as well. He held this position until 1572, when he went to Rome. There is little positive biographical information about Varolio and, consequently, some difference of opinion as to whether or not he went to Rome upon invitation to join the medical faculty of the Sapienza, the papal university. Contrary to former positive assertions, Varolio’s name appears not to have been listed in the rotuli of that institution. Moreover, there is also question as to whether he had been invited to become the physician or surgeon of Pope Gregory XIII or, indeed, had any appointment at all in the papal medical service. In any case, Varolio was esteemed by the pope and enjoyed his patronage during the three years that he was in Rome. According to a contemporary commemorative inscription– which refers to Varolio’s anatomical lectures and demonstrations “in gymnasio Romano”–he is declared to have died “from an unknown ailment.”
During his short life Varolio wrote two books, De nervis opticis nonnullisque alüs praeter communem opinionem in humano capite observatis (Padua, 1573), illustrated with three views of the brain drawn by the author, and the posthumously published Anatomiae sive de resolutione corporis humani libri IIII (Frankfurt, 1591), which has been described as a teleologic physiology of man, but which contains a reprint of De nervis opticis. It has furthermore been asserted that Varolio was the author of a work entitled De cerebro, published at Frankfurt in 1591, and of a large anatomical treatise in four books with many illustrations that was being printed at the time of his death. Neither attribution appears to be correct; in both instances there was apparently confusion with the existing posthumous Anatomiae libri IIII, which contains no illustrations except for the three figures of the brain that appeared originally in the earlier work of 1573.
De nervis optics, the source of Varolio’s anatomical reputation, consists of a letter to Girolamo Mercuriale dated 1 April 1572, the latter’s reply, and a response by Varolio. The book was published without Varolio’s consent or knowledge throught the efforts of Paolo Aicardi, a disciple of Mercuriale.
From Galenic times onward the brain had been dissected in situ by means of a series of horizontal slices begun at the uppermost part of the cerebral hemispheres. Varolio, “considering most organs of the brain to be near the base of the head, and the brain by its weight, especially in the dead body, to compress them between itself and skull,” judged the usual method of dissection “to be hindered by many obstacles.” In consequence he used a new method by which he first removed the brain from the skull, turned it over, and dissected it from below, beginning at its base. “If one proceeds in this way,” he wrote, “each of [the brain’s] organs may be observed as completely as desirable.” Although he referred to his new method of dissection as “unusual” and “very difficult,” it did permit a better observation of the structures of the brain, notably the cranial nerves, and was widely followed. It was in consequence of his new technique that Varolio was able for the first time to observe and describe the pons, still known as the pons varolii, so called because the spinal marrow was “carried under this transverse spinal process as a flowing stream is carried under a bridge.” Although Varolio considered the pons to be part of the cerebellum, it has more recently been attributed to the brain stem.
As a result of this new method of dissecting the brain, Varolio was able to make some contributions to the knowledge of the course and terminations of the cranial nerves. In the instance of the optic nerve, which provided the title of the book, he traced its course approximately to the true termination. He also suggested that the spinal cord had four tracts, two anterior serving sensation and two posterior for cerebellar functions.
Varolio’s two books, mentioned above, are very rare, De nervis opticis especially so. This work has been reprinted in facsimile (Brussels, 1969).
Works giving biographical information about Varolio are scanty and many data must be used with caution. They are, in chronological order, Gaetano Marini, Degli archiatri pontifici, I (Rome, 1784), xxxviii, 429: Giovanni Fantuzzi, Notizie degli scittori bolognese, VIII (Bologna, 1790), 158–160; Michele Medici, Compendio storico della Scuola Anatomica di Bologna (Bologna, 1857), 84–90: Umberto Dallari, I rotuli dei lettori legisti e artisit dello Studio Bolognese dal 1384 al 1799 II (Bologna, 1889), 176, 179, 182: and Ludwig Choulant, History and Bibliography of Anatomic Illustration, Mortimer Frank, trans. (Chicago, 1920), 214–215. There is also some information on Varolio as an anatomist in Antoine Portal, Histoire de I’anatomie et de la chirurgie, II (Pairs, 1770), 28–38.
C. D. O’Malley