8 



HANDBO(iK OF PHYSIOLOGY 



NEUROPHYSIOLOGY I 



its nerves were what caused it to beat (31). Lower's 

 more spectacular achievement was the apparent 

 transfusion of blood, first in dog and then in man (32, 

 33). We are surprised today that the man survived as 

 long as he did, for the blood donor was a sheep. 



Thomas Willis had added to the prevalent Galenic 

 ideas of nervous function the concept that the soul 

 had two parts which he likened to a flame in the vital 

 fluid of the blood and a light in the nervous juice. 

 When they met in the muscle, they formed a highly 

 explosive mixture which inflated the muscle. Yet even 

 before the seventeenth century had run out, a voice 

 was raised against such visionary explanations. Sten- 

 sen (34)' '^he great Danish anatomist, writing from 

 Florence in 1667, stated unequivocally that "Animal 

 spirits, the more subtle part of the blood, the vapour 

 of blood, and the juice of the ner\-es, these are names 

 used by many, but they are mere words, meaning 

 nothing." 



The seventeenth century, or grand siecle as it was 

 known to Europe, had been gloriously opened by 

 the De Magnete and gone on to the achievements of 

 Galileo, Kepler, Huygens, Leibniz and Newton, and, 

 although these were essentially achievements in 

 mathematics, physics and astronomy, all branches of 

 science were fermenting with the implications of these 

 disco\'eries. The break with dogma was now more 

 than a crack, though the Index Librorum Prolnb- 

 itorutn fought a delaying action. The men of the 

 arts were liberal in their championship of the scientists. 

 John Milton's Areopagitica (35) is a clarion call for 

 freedom of knowledge and distribution of books. 

 Milton was a young contemporary of Galileo and 

 went to see him in his old age. There is a poignancy 

 about this visit to the old blind astronomer from the 

 poet about to become blind. 



The students of the nervous system had the hardest 

 fight against dogma for in their province lay the 



31. Lower, Richard (1631-1691). Tractatus de Corde item de 

 Motu & Colore Sanguinis el Chyli cum Transitu. London: 

 AUestry, i66g; English translation by K. J. Franklin. 

 Early Science in Oxford. Oxford, 1932, \ol. g. 



32. Lower, R. The method observed in transfusing the blood 

 out of one live animal into another. Phil. Trans, i : 353, 

 1665-6. 



33. Lower, R. and E. King. An account of the experiment 

 of transfusion, practised upon a man in London. P/ul. 

 Trans. 2: 1557, 1667. 



34. Stensen, Nicholas (1638- 1686). Elernentorum myologiae 

 .'Specimen. Florence: Stella, 1667, p. 83. 



35. Milton, John (1608-1674). Areopagitica. A speech for the 

 Liberty of Unlicensed Printing to the Parliament of England. 

 1644. 



structures most suspect as being the guardians of 

 man's soul. But ranked behind them and influential on 

 them were some of the greatest philosophers of their 

 time. Prominent among the.se was Locke (36), the 

 father of empiricism. Born in the West of England and 

 trained as a physician, this man with his colorless 

 personality and his clumsy prose was to channel the 

 efforts of the next several generations of workers on 

 the nervous system into a .search for the physiology 

 of the mind. For his Essay on Humane Understanding 

 he received immediate recognition and monetary 

 reward, obtaining for it more than was paid to John 

 Milton for Paradise Lost. 



Straddling like a colo.ssus the division between the 

 seventeenth and eighteenth centuries is Newton, 

 friend and correspondent of Locke, though to .scien- 

 tists it is perhaps a bit disappointing to find that the 

 subject of their correspondence was the interpretation 

 of the New Testament (biblical history was a life-long 

 interest of Newton). Newton's insight into the move- 

 ment and forces of nature led him to make some 

 tentative suggestions about the working of the nerv- 

 ous system, and these were noted by the physiologists 

 of the time. There is scarcely a single neurophysiolo- 

 gist of the eighteenth century who does not explicitly 

 attempt to align his findings with these conjectures 

 of Newton. 



In the General Scholium (37) which he added to 

 the second edition of the Principia (26 years after its 

 first publication), Newton included a speculation. 

 This was the idea of an all-pervading elastic aether 

 "exceedingly more rare and subtle than the air," 

 which he again suggested in the form of a question in 

 the .series of Queries added to the second English edi- 

 tion of his Opticks (38). Applying this suggestion to 

 the nervous system, he said, "I suppose that the Capil- 

 lamenta of the Nerves are each of them solid and 

 uniform, that the \ibrating Motion of the Aetherial 

 Medium may be propagated along them from one 

 End to the other uniformly, and without interrup- 

 tion. . . ." It is easy to understand how eagerly such a 

 statement would be received by those who accepted 

 the idea of a nervous principle running down the 

 nerves but were worried that they knew of no fluid 

 sufficiently swift and invisible. Newton's rather sketchy 

 suggestion was therefore eagerly embraced by many 

 of his contemporaries, one of whom, Bryan Robinson, 



36. Locke, John (163J-1704). An Essay concerning Humane 

 Understanding. London: Holt, 1690. 



37. Newton, Isaac (1642-1727). Principia. London: 1687; 

 edition with General .Scholium, 171 3. 



38. Newton, L Opticks (2nd ed., 24th Query). London: 1717. 



