332 SCIENCE PROGRESS. 



elementary components — a question of no small interest 

 from quite another point of view — but the building up of 

 single parts into a whole was his mode of describing a 

 machine, thus leading to a knowledge of its powers. 



Thus it has come to pass, that the arrangement of the 

 blood-vessels in nearly all the parts of the body has been 

 studied by Ludwig and his pupils, especially in the kidney, 

 the eye, the muscle, the various glands, the small intestine, 

 the ear, the skin and the larynx. His descriptions of the 

 special patterns of circulation special to particular organs 

 awaken distinct conceptions of a most wonderful machinery ; 

 he used in his lectures to deduce some of the most intricate 

 functions of the organs from anatomical facts about the 

 vascular apparatus and in a most forcible manner. His 

 theory of the mechanism of the secretion of urine, for 

 instance, is to a great degree based on the insight which 

 his studies on the structure of the kidney afforded him. 

 It was his genius for mechanical anatomy that led him to 

 investigate the lymphatic system, where he showed that with 

 its network of delicate and minute vessels honeycombing 

 the tissues throughout the major portion of the body it 

 forms an apparatus, worked and regulated by mechanical 

 rules. He often used to urge that the anatomy of muscle 

 should be treated as a chapter of dynamics, and the re- 

 searches of Braune and Fischer have in a very promising- 

 manner been conducted according to his principle. His 

 keen appreciation of anatomical facts guided him in de- 

 vising methods previously unexampled in precision by which 

 light was shed on the functions and structure of the spinal 

 cord, and numerous special centres were discovered in the 

 medulla oblongata. I have tried to show that it was char- 

 acteristic of him to open out to auxiliary sciences and to 

 their methods distinct physiological applications. No better 

 instance can be quoted than the method, the working out 

 of which he entrusted to his pupil the now celebrated 

 neurologist Flechsig. By this method, his own discovery, 

 Ludwig by means of a pupil obtained new facts of first-rate 

 importance for the physiology of the brain and spinal cord. 

 Unlike the methods of embryology as handled by mor- 



