H 



HANDBOOK OF PHYSIOLOGY 



CIRCULATION I 



clearly indicated the way in which the heart valves 

 work, he had not carried out the implications of his 

 observations. The authority of Aristotle was unques- 

 tioned as to the finiction of the heart in supplying 

 vital spirits to the body, by the boiling of nutritive 

 spirits with air, and the lungs were considered to be 

 chiefly for the purpose of cooling the blood. This 

 notion seems to have been explored more fully by the 

 Arab physician, Ibn-al-Nafis (d. 1289), who de- 

 scribed the pulmonary circulation anatomically, and 

 indicated its function in cooling the blood, putting 

 air into it, and removing "fuliginous vapors." But 

 this work seems to have been little appreciated until 

 it was resurrected by Mohyi el Dinel Tatawi for his 

 Breisgau thesis in 1924, and analyzed by Max 

 Meyerhof in 1933.' 



It also is strange that the remarkable drawings and 

 notations of Leonardo da Vinci on the heart and 

 vessels seem to have had so little influence in their 

 time. These not only indicate the direction of blood 

 flow through the heart valves, but also show the 

 eddies and movement of blood in the large arteries. 

 Leonardo himself was so l:)ound by tradition that he 

 could not see the truth under his own eyes, skilled 

 hydraulic engineer though he was. It may be, how- 

 ever, that his anatomical drawings had more influence 

 than we realize. 



In his great description of the structure of the 

 human body in 1543, Andreas Vesalius (1514-1564) 

 raised doubt about the idea that there are tiny pores 

 in the septum of the heart. Leonardo had shown the 

 pores in the septum, but not as though they go right 

 through the septum. This was the question raised by 

 Vesalius. Now Vesalius was teaching at Padua, not 

 far from where Melzi, the devoted pupil of Leonardo, 



' E. D. Coppola (Bull. Hist. Med. 31: 44-77, 1957) suggests 

 that Andrea Alpago (died 152 1 after studying 30 years in the 

 Near East) had translated Ibn-al-Nafis, and that R. Columbo 

 (1516-1559) and his pupil, Juan Valverde (fl. mid-i6th cen- 

 tury), may have known of the translation through Andrea's 

 nephew, Paolo (died 1553?), who had studied at Padua. 

 Actually Valverde's volume (Historia de la cotnposicibn del cuerpo 

 humano, Rome, 1556) contains a description of the pulmonary 

 circulation probably derived from Columbo, although pub- 

 lished before Columbo's De re anatomica appeared in 1559. An 

 excellent study of Ibn-al-Nafis has been made by E. E. Bittar 

 (Bull. Hist. Med. 29: 352-368, 429-447, 1955). Both Coppola 

 and Bittar were Yale pupils of John F. Fulton (1899-1960), who 

 stimulated so many to do so much in the history of physiology 

 and medicine. In his characteristically keen manner, C. D. 

 O'Malley (J. Hist. Med. 12: 248-253, 1957) analyzes the evi- 

 dence regarding the anti-Galenical ideas of Ibn-al-Nafis as 

 appearing in Andrea Alpago's Avicenna phitosophi, as published 

 by Paolo in Venice in 1546. 



was keeping the master's drawings, and showing them 

 on occasion to friends or visitors who might be in- 

 terested. Certainly the existence and value of these 

 manuscript drawings must have been well known 

 around the area. Indeed it is not impossible that 

 \'esalius was stimulated to illustrate his description 

 of the structure of the human body in the grand man- 

 ner suggested by the Leonardine anatomical drawings. 

 Later, around 1600, when the cultured Fabricius 

 (1537- 16 1 9) had built the anatomical theater at 

 Padua that \"esalius dreamed about, he had as his 

 pupil working with him on the development of the 

 chick, the young Englisliman, William Harvey. Could 

 it be that one holiday they went over to the old Melzi 

 villa to look at Leonardo's anatomical sketches? 



It is intriguing to speculate on how Leonardo's 

 great treasure of anatomical notes came to England. 

 Perhaps Harvey, when traveling with Lord Arundel 

 to Vienna in 1636, learned that the Melzi heirs were 

 dispersing the Leonardo drawings. Harvey came o\er 

 to Italy, and was quarantined in Venice for a couple of 

 weeks, when he had to rush back to Vienna. For what 

 had he made this sudden trip? Later when Lord 

 Arundel was in Spain, he acquired the Leonardo 

 anatomical sketches, and had them sent hurriedly 

 to Windsor Castle, where they stayed. How was it 

 that he realized their value, and secured them for 

 England? Could it have been that Harvey had seen 

 them while studying at Padua, and that they had 

 given him a hunch or two about the heart valves? 



It is as difficult to assess the influence of Miguel 

 Serveto (Servetus) (1511-1553) in regard to the 

 pulmonary circulation as it is to appraise the eflfect 

 of Leonardo's anatomy on his contemporaries. 

 Servetus was a stormy figure; a fellow student at 

 Paris with Vesalius, he had written on medicinal 

 preparations, and then become involved in churchly 

 arguments. He incurred the suspicion of the authori- 

 ties when he wrote on the errors of the Trinity. Driven 

 by some inner conviction he pursued the matter in a 

 volume, Christianismi restitulio, which he realized \vas 

 too much for the Roman Church. He took the page 

 sheets to Geneva, hoping to find protection with 

 another fellow student from Paris, the reformer John 

 Calvin. Calvin, however, tried and condemned him 

 for heresy, and he was burned in 1553, supposedly 

 with all copies of the work. Three escaped the flames. 

 Amazingly the book contains a concise description of 

 the lesser circulation. It is doubtful that his notions 

 could have been appreciated. 



In the anatomy of Realdus Colombo (1516-1559) 

 published the year of his death, there is again a con- 



