THE HISTORICAL DEVELOPMENT OF NEUROPHYSIOLOGY 



FIG. 2. Borclli and one of his sketches to show the center of 

 gravity of man when carrying a load. (From BorelU, G.A. De 

 Mntu Animalium, 2nd ed., Leydon : Gaesbeeck, 1685.) 



motion result are brought about as light is in air, 

 perhaps as the flu.x and reflu.x of the sea." 



That nerves might play a role in the working of 

 the heart as a mechanical pump was first suggested 

 by Borelli the Neapolitan, professor of mathematics at 

 Pisa and later at Florence, who applied the reasoning 

 of his discipline to physiology and e\olved mechani- 

 cal models for various bodily functions. His concept 

 of the innervation of muscle was an initiation by the 

 nervous fluid ('succus nervcus') of a fermentation in 

 the mu.scle swelling it into contraction, for there were 

 still many years to go before a dynamic concept of 

 muscle was to emerge in spite of Harvey's demon- 

 strations on the heart. Peripheral muscles were still 

 regarded as passive structures rather like balloons to 

 be inflated by nervous fluid or gaseous spirits reach- 

 ing them through canals in the nerves. Borelli, by 

 an ingenious experiment in which he submerged a 

 struggling animal in water and then slit its muscles, 

 demonstrated that the spirits could not Ije gaseous 

 since no bubbles appeared in spite of the violent 

 contractions. It was this experiment that led him to 

 the suggestion of a liquid medium from the nerve, 

 mixing in the muscle to cause a contraction by ex- 

 plosi\e fermentation ('ebuUitio et displosio') (19). 



Giovanni Alphonso Borelli was a member of the 

 group of experimental scientists banded together in 

 the Accademia del Cimento under tlie patronage of 

 the .science-loving Medici brothers in Florence. This 

 small .scientific society, successor to the Lincei, existed 

 for only a decade but was typical of the independent 



ig. Borelli, Giovanni .Alfonso (1608-1679). De molu ani- 

 malium (pubUshed posthumously). Rome: Bernado, 1680- 

 I ; a small section has been translated into English by 

 Michael Foster. Lectures on the History of Physiology. Cam- 

 bridge: Cambridge, 1901. 



groups centered on laboratory experiment that were 

 to spring up in independence of the universities where 

 the scholars had still not looked up from their books. 

 Few as they were (there were only nine members) 

 these laboratory scientists of the Accademia were to 

 have a far-reaching though delayed influence on 

 European thought, for in the final year of the acad- 

 emy's existence they published their proceedings (20). 

 Founded entirely on empirical methodology, this was 

 a truly scientific text. It was, however, written in 

 Italian although soon translated into English, and it 

 did not reach the scientific world at large until Petrus 

 van Musschenbroek of Leydeii made a Latin transla- 

 tion (21). It was this book that, for example, influ- 

 enced Stephen Hales so greatly in his experimental 

 work. The volume included only one series on animal 

 experimentation, but almost all the rest deals with 

 the physics which are basic to the work a physiologist 

 does in his laboratory. 



To his contemporary, Descartes, Borelli owed his 

 application of mathematics to muscular action. This 

 pungent philosopher, who rarely did an experiment, 

 wrote a text that was to influence all experimenters, 

 The Discourse on Method (22). It is not experimental 

 method that he discusses, i)ut his own method of 

 thought, his theory of knowledge." Scientists had 

 just begun to look around them to olaserve nature 

 and to let the statements about her by the ancients 

 lie in the books when they had to meet a new and 

 brilliant challenge; mathematics was the tool they 

 were to use. Mathematics would not only elucidate 

 the laboratory experiment but would provide the 

 basis for an all-embracing theory of science. 



This great man bred in the gentle landscape of 

 Touraine was to devote his life to a search for the 

 truth, .seeking for himself a quiet environment for 

 free thinking.' This he found for 25 years in the 



20. Saggi (It naturali esperienrji fattr nell Aecadeniui del Cimento, 

 edited by L. Magalotti. Florence, 1667; translated into 

 English by Richard Waller. Essayes of Natural Experiments 

 made in the Accademie del Cimento. London, 1684. 



21. VAN Musschenbroek, Petrus (1692-1761). Testamina 

 Experimentortum Naturaliuin captoruni in Accademia del Ci- 

 mento. Leyden, 1731. 



22. Descartes, R. Discours de la Methode. 1637 ^ English trans- 

 lation by E. S. Haldane and G. R. T. Ross. Philosophical 

 Works of Descartes. Cambridge : Cambridge, 1 904. 



* "Methode de bien conduire sa raison, pour trouver la 

 verite dans les sciences." 



' "Cum nil dignum apud homines scientia sua invenisset, 

 eremum ut Democritus aliique vcri Philosophi elegit sibi 

 juxta Egmundum in HoUandia, sibique solitarius in villula per 

 25 annos remansit, admirandaque multa meditatione sua 

 detexit" (Borel, p. 9). 



