36 Harvey and the [lect. 



or rather village bearing that name, Fabricius studied under 

 Falloppius at Padua, and, on the death of his master, in 1565, 

 succeeded him in the chair of Anatomy, holding it for 40 years, 

 until 1619, when he died at the ripe old age of 82. 



A distinguished surgeon and a learned anatomist, well 

 acquainted with the anatomy not only of man but of other 

 vertebrates, he was the author of man} 7 treatises, most of which 

 had distinct physiological bearings and which contained many 

 contributions to the advancement of knowledge. He was the 

 first after Aristotle to describe the formation of the chick in 

 the egg ; he wrote well on locomotion, on the eye, on the ear, 

 on the skin, on the larynx and on speech ; but the one work 

 which concerns the subject which we have in hand is that on 

 the valves of the veins, the book De venarum ostiolis, 'the 

 little doors of the veins,' which saw the light in 1574. 



Johannus Baptista Cannanus, Professor at Ferrara, is said to 

 have observed the valves long before, namely in 1547, and 

 indeed to have told Vesalius of his observation ; and even 

 before that, these structures it is said were noticed by Sylvius. 

 But they were not really laid hold of until Fabricius published 

 his book. In that work he most carefully and accurately 

 described their structure, position and distribution, illustrating 

 his observations by fairly good figures. He moreover clearly 

 recognized that the valves offered opposition to the flow of 

 blood from the heart towards the periphery, and even gives 

 the now well-known demonstration of their action on the living 

 arm. 



He says De, Venarum Ostiolis : 



" Little doors of the veins is the name I give to certain very 

 "thin little membranes occurring on the inside of the veins, 

 " and distributed at intervals over the limbs, placed sometimes 

 "one by itself, and sometimes two together. They have their 

 " mouths directed towards the root of the veins (i.e. the heart), 

 " and in the other direction are closed. Viewed from the outside 

 " they present an appearance not unlike the swellings which are 

 " seen in the branches and stem of a plant. In my opinion they 

 "are formed by nature in order that they may to a certain 

 " extent delay the blood and so prevent the whole of it flowing 



