200 HISTORICAL. 



creditur, sed magno artificio a cordis dextro ventriculo, longo per pulmones ductu, 

 agitatur sanguis subtilis; a pulmonibus praeparatur, flavus efficitur et a vena 

 arteriosa (Arteria pulmonalis) in arteriam venosam (Venae puimonales) trans- 

 funditur." Almost a quarter of a century later, in 1589, Caesalpinus traced the 

 course of the greater circulation. He was the first to use the word "circulation." 

 Later, Fabricius ab Aquapendente (Padua, 1574) also recognized and confirmed 

 the centripetal movement of the blood in the veins (which until that time was 

 almost universally believed to be centrifugal, although Vesalius was familiar 

 with the centripetal current in the main trunks) from the position of the valves 

 in the veins, of which he made an accurate study, although they had been men- 

 tioned in the middle of the fifth century after Christ by Theodoretus, Bishop of 

 Syria, also by Sylvius, by Vesalius (1534) and by Canani (1546) . William Harvey, 

 a pupil of Fabricius (until 1604), finally constructed, between the years 1616 and 

 1619, partly from his own investigations and partly from the results of former 

 observers, the picture of the circulation of the blood, the greatest physiological 

 achievement, which was published in 1628 and marks a new epoch in physiology. 



With respect to individual features of the vascular system, the following is 

 yet worthy of mention: According to Hippocrates the heart is a fleshy organ and 

 the root of all the vessels ; he was familiar with the large vessels originating from 

 the heart, the valves, the chordae tendineag, the auricles, and the closure of the 

 semilunar valves. Aristotle first named the aorta and the venae cavae, the school 

 of Erasistratus the carotid; the latter also explained the function of the venous 

 valves. In Cicero mention is made of the distinction between arteries and veins. 

 Celsus, in the fifth century after Christ, pointed out that the veins, when opened 

 below a compressing bandage, bleed. Aretaeus (50 A. D.) knew that arterial 

 blood is bright red and venous blood dark. Pliny (died 79 A. D.) described the 

 pulsating fontanel in man. The presence of a bone in the septum of large mam- 

 mals (ox, stag, elephant) was known to Galen (131203 A. D.). In his opinion 

 the veins ultimately communicate with the arteries by means of the finest tubes, 

 and this view was later confirmed by de Marchettis (1652) and Blancard (1676) 

 with the aid of injections, and by Malpighi, who made microscopic observations 

 of the circulation of the blood in cold-blooded animals, as well as by William 

 Cowper (1697) , who made similar observations on warm-blooded animals. Stenson, 

 who was born in 1638, first demonstrated the muscular nature of the heart, al- 

 though a statement to like effect had already been made by the Hippocratic and 

 Alexandrian schools. Cole demonstrated the progressive increase in the width of 

 the arterial area as the capillary region is approached. Joh. Alfons Borelli (1608 

 1679) was the first to estimate the power of the heart according to the laws of 

 hydraulics. Craanen, in 1685, described systolic contractions in the pulmonary 

 veins;. Leeuwenhoeck (1694) the anatomical arrangement of the heart-muscle 

 fibers among themselves. Chirac, in 1698, ligated a coronary artery of the heart 

 in a dog, without, it is true, producing any result. 



According to Aristotle, turtles can live for a short time after the heart has 

 been removed. 



Many of the ancients (the Israelites, Empedocles, Kritias, Lucretius) believed 

 that the vital principle of the body, and even the soul (Aristotle and Galen) , had 

 its seat in the blood. Aristotle was familiar with the poisonous effects of the 

 vapor of burning charcoal; Porcia voluntarily chose to die by inhaling it. Vene- 

 section was practised by Greek physicians soon after the Trojan war. 



The iron in the red blood-corpuscles was discovered by Menghini in 1746. 



