GROUND-AIR IX ITS HYGIENIC RELATIONS. 293 



There is not one among these departments of hygiene in which 

 nothing is left to be done; in most of them the work has scarcely- 

 begun. There has always been a desire for and an aiming at health ; 

 but ideas about it have changed completely. The former supports 

 of hygiene have crumbled away in the powerful analytical solvents 

 of modern physiology; very little has remained; everywhere new 

 foundations are necessary. This requires workmen ; the season ap- 

 pears favorable do not let it pass unemployed. 



It is not sufficient to build up correctly a series of hygienic truths, 

 which might be the work of a few ; these truths must be brought to 

 bear upon life, and this requires instruments. Three professions are 

 in real life the natural trustees and representatives of the hygienic 

 interests of the community physicians, architects, and engineers, 

 and also the public administration. There must be harmonious 

 action between them; good intentions are not sufficient; there must 

 be knowledge and power. Only good musicians can make good 

 music, and they must be well taught and practised. The institutions 

 at which the members of these professions have received their educa- 

 tion have all the while generally ignored hygiene as an independent 

 branch of study. A vague supposition left it to the individuals con- 

 cerned to take the ti'ouble of gathering for themselves whatever was 

 known or would be made public about matters of hygiene. Lectures 

 on forensic medicine were supposed to be sufficient, but they have to 

 consider facts and evidence only with regard to penal laws, which 

 themselves result from the old and highly-cultivated science of juris- 

 prudence. Hygienic laws must spring from hygienic science, and 

 there was none. 



Many of the existing hygienic laws and regulations cannot be 

 kept up if examined by the light of hygienic science as it is now. 

 It is no good going on issuing public regulations, demonstrative of 

 good intentions, for the public health ; the right thing is to create 

 a firm basis for practical purposes and public measures. Hygiene 

 must become an independent branch of study, to be taught by special 

 teachers at universities, medical and polytechnic schools, not without 

 the help of proper laboratories. Systematic instruction must be 

 offered to students and practitioners of medicine, to members of the 

 civil or municipal service, to architects and engineers. Books and 

 reading can as little occupy the place of personal teaching and ex- 

 perimental investigation as a medical book in the library that of the 

 physician, or a hand-book that of the public chair. The self-taught 

 hygienist has frequently to look out for principles on which to act, 

 while he is called upon to act at once, and routine alone is a danger- 

 ous and unreliable assistant. There are exceptions brilliant ones 

 even but exceptions prove the rule. 



The increasing interest taken by the intelligent and well-meaning 

 members of society in matters of public health, which have also an 



