i86 BIOLOGY AND ITS MAKERS 



to make physiology broadly comparative. So comprehensive 

 was his grasp upon the subject that he gained for himself 

 the title of the greatest physiologist of modem times. He 

 brought together in his great work on the physiology of man 

 not only all that had been previously made known, carefully 

 sifted and digested, but a great mass of new information, 

 w^hich was the result of his own investigations and of those 

 of his students. So rigorous were his scientific standards 

 that he did not admit into this treatise anything which had 

 been untested either by himself or by some of his assistants 

 or students. Verworn says of this monumental work, which 

 appeared in 1833, under the title Handhuch der Physiologie 

 des Menschen: "This work stands to-day unsurpassed in 

 the genuinely philosophical manner in which the material, 

 swollen to vast proportions by innumerable special researches, 

 was for the first time sifted and elaborated into a unitary 

 picture of the mechanism within the living organism. In this 

 respect the Handhuch is to-day not only unsurpassed, but 

 unequalled." 



Mliller was the most accurate of observers; indeed, he is 

 the most conspicuous example in the nineteenth centur}^ of a 

 man who accomplished a prodigious amount of work all of 

 which was of the highest quality. In physiology he stood on 

 broader lines than had ever been used before. He employed 

 ever\^ means at his command — experimenting, the observa- 

 tion of simple animals, the microscope, the discoveries in 

 physics, in chemistry, and in psychology. 



He also introduced into physiology the principles of psy- 

 chology, and it is from the period of Johannes JMiiller that 

 we are to associate recosrnition of the close connection be- 

 tween the operations of the mind and the physiology of the 

 brain that has come to occupy such a conspicuous position 

 at the present time. 



Muller died in 1858, having reached the age of fifty-seven, 



