842 THE POPULAR SCIENCE MONTHLY. 



upon health, and of the physical relations of clothing. In short, this 

 new domain of knowledge opened itself to him on all sides. The 

 conviction had grown up in Germany that the care a people takes 

 for its public health may be regarded as an index of its advance in 

 civilization. This care, he taught, concerns not only the healing of 

 diseases, but even more the guarding against them ; by the side of the 

 care for the sick should stand a regard for the preservation of health, 

 which should avail itself of the most recent results of science, and 

 should be exercised by the state as one of its most pressing duties. 

 That these views so made their way in Bavaria that professorships of 

 hygiene, of which he was assigned to that in the University of 

 Munich, were established in the high-schools of that kingdom, was 

 mainly due to Pettenkofer ; and the interest in hygienic matters, 

 which was minifested in other ways, was excited chiefly by his 

 motion. 



Hygiene of course acquired an increased importance during epi- 

 demics, when disease threatened not individuals only, but whole cities 

 and countries. With this category we enter upon the region which 

 Pettenkofer has made the objective point of his activity. The investi- 

 gations which he published on the nature and spread of the cholera 

 enjoy an authority that is hardly limited by geographical boundaries. 

 Here, indeed, Science has to contend with many unknown factors, and 

 we should contradict the views of our active investigator himself if 

 we should assume to speak of conclusive results. Nearly all in the 

 present theories is provisory ; the most varied points of view are op- 

 posed one to another ; but, notwithstanding this, the beginnings that 

 have been made, and the few fixed points that have been verified 

 with respect to the questions, are a priceless gain. Hardly any other 

 kind of affliction, observes Dr. Stieler, has been in the past so sur- 

 rounded with superstitions as that of great epidemics. Thousands of 

 persons were murdered in the middle ages on charges of poisoning 

 wells; and, even after this kind of barbarism had disappeared, the terror 

 remained which every danger excites, before which we stand ignorant 

 and defenseless. We have now entered an age of correct discernment ; 

 intelligent investigation has taken the place of superstitious fear, and 

 has neutralized its grievous effects by seeking and finding out natural 

 causes. The ghostly element which seemed peculiar to these diseases 

 has been destroyed, for it is no longer able, after the fashion of ghosts, 

 to evade every attack, but has been made accessible and tangible, like 

 every other enemy. Dr. Pettenkofer has had a great part in bringing 

 about the revolution that has taken place, by taking hold of the ghosts, 

 as it were, and compelling them to stand and receive his attacks ; and, 

 instead of resigning himself to their supposed machinations, he has 

 taken the chief and leading part in contending against them. His 

 researches have established, however much we may still contend re- 

 specting the ultimate origin of cholera, that three conditions appertain 



