KNOWLEDGE IN ANCIENT TIMES n 



he made some unfortunate mistakes concerning the 

 vascular system. Thus he attached enormous and ex- 

 aggerated importance to the heart. Not only did he and 

 his successors rightly regard it as the centre of the vascular 

 system, but they also attributed to it various other 

 qualities and functions that we now know it does not 

 possess. They regarded the heart as the seat of the in- 

 telligence and the source of the bodily heat. Moreover, 

 they considered that, during the process of development, 

 the heart was the first organ to develop, while at death 

 it was the last organ to show activity. These views have 

 since been shown to be erroneous. 



Soon after the time of Aristotle, and about 300 B.C., 

 a great medical school was founded at Alexandria in 

 Egypt. That country had been conquered by Alex- 

 ander the Great, after whom the town Alexandria was 

 named. On Alexander's death, Egypt came under the 

 rule of one of his generals, Ptolemy, who founded a 

 dynasty which became extinct in the time of Julius Caesar 

 with the famous Queen Cleopatra, just before the 

 Christian era. 



The town of Alexandria, though in Egypt, was a 

 favourite residence of this Greek dynasty, and became 

 more Greek than Egyptian. Ptolemy and his successors 

 were disposed to encourage learning, and at the medical 

 school at Alexandria very remarkable physiological re- 

 searches were made. These were entirely the work of 

 Greek physicians, and by them the knowledge of the 

 heart and the vascular system was placed on a more 

 scientific basis. Thus there arose in Alexandria a tradi- 

 tion of physiological learning and research that was to be 

 found nowhere else in the ancient world. 



About the middle of the second century A.D. there came 

 as a student to the still flourishing medical school at 

 Alexandria a young Asiatic Greek, whose views were 



