Proceedings of the Ohio State Academy of Science 44!) 



men. He still held to the old theory of Galen, viz : that the 

 ))lood flows out from the heart to the tissues in the veins and 

 refers to the valves as a mere hindrance to the flow so it would 

 iiot accumulate in the lower extremities to the detriment of 

 the upper extremities. He says "little doors of the veins" i^ 

 the name I give certain very thin membranes occurring in the 

 inside of the vein and distributed at intervals over the limbs, 

 placed sometimes one by itself, and sometimes two together. 

 They have their mouths directed toward the roots of the 

 \eins (i. e. the heart) and in the other direction they are 

 closed. Viewed from the outside they present an api)earance 

 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 at once like a flood either 

 to the feet, and to the hand or the fingers, and becoming col- 

 lected there. For this would give rise to two evils ; on the 

 one hand the upper parts of the limbs would suiTer from wani 

 of nourishment, and on the other hand the hands and the feet 

 would be trpuMed with a continued swelling. In order there- 

 fore that the -blood should be everywhere distributed in a 

 certain just measure and admirable proportion for maintain- 

 ing the nourishment of the several parts, these valves of the 

 veins were formed." It will be seen that Fabricius did not 

 grasp the true function of the valves at all. It was left for a 

 ])Upil of his to clear up the i)oints and denuMistrate their use. 

 He had many clear ideas of the process of respiration but we 

 "-till hear him speak of the air reaching the heart through the 

 \ein-like artery and of the generation of the vital spirits, "ll 

 all this belongs to tlie innate heat of the heart which burns as 

 with a flame, it must in any case be maintained that the 

 whole business of maintaining and regulating that lieat con- 

 sists in the first i)lace of ])roviding material (for the flame), 

 then for the ventilation, then of moderate refrigeration, and 

 lastlv of the discharge of the fumes; all these are sup])lied by 

 respiration." It is with winder that we sum u\) \hv works ot 



