THE BIOLOGICAL SCIENCES AND MEDICINE. 339 



diagnosis ; his physiology was too erroneous to supply 

 data for pathological reasoning. But when the Alex- 

 andrian school, with Erasistratus and Herophilus at their 

 head, turned to account the opportunities of studying 

 human structure, afforded to them by the Ptolemies, 

 the value of the large amount of accurate knowledge 

 thus obtained to the surgeon for his operations, and to 

 the physician for his diagnosis of internal disorders, 

 became obvious, and a connection was established be- 

 tween anatomy and medicine, which has ever become 

 closer and closer. Since the revival of learning, sur- 

 gery, medical diagnosis, and anatomy have gone hand 

 in hand. Morgagni called his great work, " De sedibus 

 et causis morborum per anatomen indagatis," and not 

 only showed the way to search out the localities and the 

 causes of disease by anatomy, but himself travelled 

 wonderfully far upon the road. Bichat, discriminating 

 the grosser constituents of the organs and parts of the 

 body, one from another, pointed out the direction which 

 modern research must take ; until, at length, histology, 

 a science of yesterday, as it seems to many of us, has 

 carried the work of Morgagni as far as the microscope 

 can take us, and has extended the realm of pathologi- 

 cal anatomy to the limits of the invisible world. 



Thanks to the intimate alliance of morphology with 

 medicine, the natural history of disease has, at the pres- 

 ent day, attained a high degree of perfection. Accurate 

 regional anatomy has rendered practicable the explora- 

 tion of the most hidden parts of the organism, and the 



