162 PHYSIOLOGY CHAP. 



the fact that we have no direct means of estimating the anatomical 

 knowledge of Servetus. 



He had indeed been dissector for Glinther ; but the latter was 

 a man of no originality, and his Institutiones of the year 1539 

 showed no advance on the 1538 edition of the anatomical works 

 of Vesalius, but was rather a retrogression. 



Another argument is derived from analysis of the anatomical 

 passages of the works of Servetus. His theory of the communica- 

 tions between the nerves and vessels, as conjectured by Praxagoras, 

 was confuted by Galen and Vesalius. The impermeability of the 

 ventricular cardiac septum belongs, as we have seen, to Columbus, 

 and the capacity of the pulmonary artery to an observation of 

 Vesalius. Added to this, Servetus never properly verified the new 

 anatomical observations, which he vaguely adopted; and never 

 attempted criticism of arguments contrary to his own views ; nor 

 did he bring forward any valid anatomical demonstrations in 

 support of his position. From all this but one conclusion is 

 possible. Servetus worked from books, and not from the subject ; 

 he was a compiler, not a practical anatomist. 



He pieced together the doctrine of Galen, certain ideas of 

 Praxagoras, and the observations of Vesalius ; with the discovery 

 of the latter he perfected and completed Galen's rudimentary 

 views on the pulmonary circulation ; but by quoting from 

 Praxagoras, he made a step backwards, not merely behind 

 Vesalius, but behind Galen also. In short, Servetus, animated 

 by his desire to conciliate science with the Bible, promulgated a 

 speculative, not a real anatomy, an anatomia imaginabilis, not an 

 anatomia sensibilis. 



Eoth, therefore, confirms Ceradini's statements as to the 

 priority of Columbus over Servetus, in regard to the lesser 

 circulation. 



It is interesting, again, to determine the part taken in this 

 great discovery by the Belgian Vesalius, the founder of modern 

 anatomy, to whom Flourens (1857) ascribed priority in the theory 

 of the impermeability of the septum, while the theologian Tollin 

 (1884) accused him of plagiarising from Servetus, an opinion also 

 maintained by Tigerstedt (1893). 



In the first edition of his great work, De humani corporis 

 fabrica (1543), Vesalius says that he finds himself " driven to 

 wonder at the handiwork of the Almighty, by means of which the 

 blood sweats from the right into the left ventricle through 

 passages which escape human vision." In the second edition 

 of this work, published in 1555, he omits the expression of 

 admiration for the Creator, and declares himself unable to 

 understand how " per septi illius substantiam ex dextro ventriculo 

 in sinistram ne minimum quid sanguinis assumi possit." Accord- 

 ing to Tollin, Vesalius must have derived this more accurate mode 



