154 Dr Craigie's Observations on the 



of the Stagirite, by distinguishing the arteries from the veins. 

 By teaching that the former were air-vessels, however, he con- 

 tributed to perpetuate an error, which has had more influence 

 than any other^ in retarding the progress of accurate anatomical 

 knowledge. From this circumstance, it is not unlikely that the 

 book on Respiration, ascribed to Aristotle, is the production ei- 

 ther of Praxagoras or of some of his disciples. It is further 

 a singular circumstance, that Praxagoras is the first who regard- 

 ed the brain as an efflorescence or expansion of the spinal chord, 

 an opinion which might have been suffered to rest in undis- 

 turbed tranquillity, had it not been made the basis of a very 

 elaborate theory by MM. Gall and Spurzheim. 



Erasistratus, a pupil of Chrisippus and Aristotle, distin- 

 tinguished himself by dissecting, not only the bodies of the lower 

 animals but that of the human race. He recognised the lac- 

 teals in the mesentery of the kid ; he described the semilunar 

 valves at the beginning of the aorta, and the tricuspid or triglo- 

 chin (r^tyXuxim) at the base of the right ventricle ; he demon- 

 strated the brain, and compared that of man with those of the 

 lower animals ; he shewed the nerves proceed from the brain ; 

 and he distinguished them into two classes, those of sensation 

 and those of motion. 



Herophilus, the pupil of Praxagoras, and contemporary of 

 Erasistratus, has been distinguished among the ancients as the 

 great cultivator of the anatomy of the human body. Of these 

 he probably dissected more than any of his predecessors or con- 

 temporaries. But the exaggerated statement of Tertullian has 

 been absurdly repeated by almost every author, to prove that 

 he dissected 600 corpses *. The classical reader is aware that 

 the term 600 is invariably used by the Roman authors in a ge- 

 neral hyperbolical sense to signify many, but by no means an 

 exact number, and may as likely signify 16 as 600. With 

 his dissection of the human body, however, we have at present 



• Herophilus ille, medicus aut lanius, qui sexcentos exsecuit ut naturam 

 Bcrutaretur, qui hominem odit ut nosset, nescio an omnia interna ejus liquido 

 explorarit, ipsa morte mutante quae vixerant, et morte non simplici, sed ipsa 

 inter artificia exsectionis errante. Tertullian de Anima, c. 10. p. 757* Bal- 

 nea sementis, de plQris portuus, in qua Gestetur dominus quoties pluit. Juven. 

 Sat. vii. 178. 



