CHAPTER XXVI 



PUBLIC HYGIENE, OR GENERAL SANITATION 



519. Definition. As personal hygiene is the art and the 

 science of preserving the individual body in health, so 

 public hygiene is the art and science of promoting the 

 health of the community. A healthy man is one whose 

 body is sound and vigorous in all its parts, so that all the 

 functions of the system are performed perfectly, easily, 

 and without discomfort; no one of all the organs neglect- 

 ing or failing to do the work assigned it, and so deranging 

 or poisoning other organs. 



A healthy village or city is one in which most of the 

 inhabitants are healthy, and especially one in which con- 

 tagious and infectious diseases do not pass from one per- 

 son to another. 



We have learned that a man, in order to maintain his 

 health, must have pure air, pure water, and wholesome 

 food. But in crowded towns and cities even the wealth- 

 iest citizens are not able to procure these simple necessities 

 for themselves. The carelessness of some obscure and 

 ignorant person may poison the water supplied to rich 

 and poor alike ; germs of disease from the most squalid 

 part of a city may be borne by the air, by the gas of a 

 sewer pipe, or in any one of a thousand other ways to 

 carry death to a palace many miles away. A single filthy 

 dwelling may poison a whole town. It is not enough 



