10 PATHFINDERS OF PHYSIOLOGY 



cardiac septum. He had grasped the true features of the pulmonary 

 circulation — the passage of the blood from the right side to the 

 lungs, thence to the left side or ventricle. Realdus Columbus, bom 

 at Cremona, 1516, a presumptuous personage, speaks of the blood 

 carried, "by the artery-like vein to the lung and being there made 

 thin is brought back thence together with air by the vein-like artery 

 to the left ventricle of the heart." Then he goes on to press his claim 

 by declaring that, hitherto, no one had made this observation or re- 

 corded it in writing. Andreas Caesalpinus Was bom at Arezzo in 

 1519. He held for many years the professorship of medicine at Pisa. 

 Learned in all the lore of the ancients, he was noted among other 

 things for his determined opposition to Galen; Caesalpinus appears 

 to have grasped one important truth, namely, that the heart at systole 

 discharges its contents into the aorta and pulmonary artery, and at 

 its diastole receives blood from the vena cava and pulmonary vein. 

 Let all this be granted, yet the great work of Harvey is not a 

 whit less meritorious. The steam engine was in existence before the 

 day of James Watt, yef his name is inseparably associated with the 

 invention which transformed a mere toy into a gigantic factor which 

 has revolutionized human industry. No person, not even the genius is 

 independent of his time ; he is the heir of all the ages, and his great- 

 ness does not depend so much in presenting something unprecedented 

 as it does in seeing something clearly and tening_in^.jL.simple way 

 what he has seen. ^.-^'^"'^^^^^^^ ^^^ 



Treatise on the Circulation. — Harvey's greatest work was un- 

 doubtedly his Exercitatio Anatomica de Motu Cordis et Sanguinis in 

 Animalibus, an anatomical treatise on the movement of the heart 

 and blood in animals, published in Frankfort, Germany, in 1628. The 

 book was a small quarto volume of 72 pages. It opens with a dedi- 

 cation to "The Most Illustrious and Indomitable Prince, Charles, King 

 of Great Britain, France, and Ireland, Defender of the Faith," etc. 

 The dedication proceeds : "The heart of animals is the foundation of 

 their life, the sovereign of everything within them, the sun of their 

 microcosm, that upon which all growth depends, from which all 

 power proceeds. The king in like manner, is the foundation of his 

 kingdom, the sun of the world around him, the heart of the republic, 

 the fountain whence all power, all grace doth flow." Whatever may be 

 said regarding Charles I, who was the victim of public execution, he 

 certainly befriended Harvey. Then to the president of the Royal Col- 

 lege of Physicians and to other learned physicians the author ad- 

 dresses himself in a dedication which he concludes : *****! profess 

 both to learn and to teach anatomy not from books but from dissec- 

 ^tions; not from the positions of philosphers but from the fabric of 

 nature. * * * I avow myself the partisan of truth alone: and I can 

 indeed say that I have used all my endeavors, bestowed all my pains 

 on an attempt to produce something that should be agreeable to the 

 good, profitable to the learned, and useful to letters." Harvey's 

 method here ennunciated is the method of every scientist since his 

 day, whose contribution has possessed real meri1> — that is, reasoning 

 based upon experiment and observation. ^^--^ ^n 



The work on the circulation comprises seventeen short chapter's. 

 It is an interesting account, lucid and connected, of the heart's' action 

 and the circulation of the blood. Harvey had no means of knowing 



