342 POPULAR SCIENCE MONTHLY. 



hand, began his presentation with a Physiology of Atoms and of 

 Conditions of Aggregation. As an ideal form of investigation, he 

 conceived the possibility of deducing the functions of complicated 

 molecules from the conditions of their elementary construction, 

 thence, however, to continue step by step to the tissues, and subse- 

 quently to the organs. Thus he thought to construct an intelligible 

 theory proceeding from the simple to the complex, and at the same 

 time to determine with mathematical accuracy the derivation of the 

 one from the other in respect to direction, time, and quantity, and to 

 prove the existence of each as the necessary outcome of a natural law. 



The theoretical need of an elementary foundation for physiology 

 caused Ludwig in his earlier years to study certain fundamental 

 physical processes, such as filtration, diffusion, and the laws of 

 hydraulics, with especial attention, and to make use of the knowledge 

 thus obtained to explain the phenomena of animal life. Later he 

 grew far more cautious as regards these explanatory experiments, 

 and references to the organic connections of vital processes are much 

 more frequent in his later work. He now speaks with especial pre- 

 dilection of the wonderful mechanism of life, the intricate workings 

 of which, in all its complications, it is the duty of science to reveal. 



I here quote a few words from the speech that Ludwig delivered 

 on entering on his professorship at this university: "Physiology," 

 he said, " has entered with full consciousness the sphere of mechanics, 

 where rigorous laws obtain, and where the inexorable logic of cir- 

 cumstances rules the course of the atoms; but we, the heavily bur- 

 dened servants of science, have armed ourselves with a thousand 

 weapons with which to pursue the intangible phenomena of Nature, 

 and, reflecting on these, we endeavor to understand the subtle mech- 

 anism of life. And when we finally receive our reward, when we at 

 last comprehend an organ in all its connections, our proud conscious- 

 ness is crushed by the knowledge that the human discoverer is but 

 a bungler beside the unknown creator of animal life. For when man 

 compares himself with him in the solution of any problem, he must 

 ever fall short, as does the telescope compared with the eye, and the 

 litmus paper with the tongue. And if all this was once clear, why 

 must it needs again become obscure to us? " 



If, however, we desire to understand Ludwig's full importance, 

 we must seek him in his laboratory, and in the midst of his pupils, 

 for here his most characteristic and noblest qualities reached their 

 fullest development. A summary of Ludwig's and his students' 

 work can only be indicated here. With his endeavor to make the 

 construction of the body physiologically comprehensible, Ludwig, 

 unlike some of his friends who were engaged in the same line of 

 work, did not confine himself merely to physical experiments, but 



