HEALTH AND SANITATION 59 



besides those associated with the holds of vessels justify 

 the belief that the growth of the poison of yellow fever is 

 specially favored in warm, moist, ill-ventilated places, 

 where air is closely confined. A special report on the 

 density of the population of Havana compared with 

 numerous other cities has shown that more than three 

 fourths of the people of Havana live in the most densely 

 populated localities in the world. A tropical climate ren- 

 ders this evil still greater. The low-lying floors touching 

 the earth, the small, densely packed houses, the unusually 

 contracted ventilating- space in their rear, the large unven- 

 tilated excavation for privies and sinks, all furnish, as is 

 firmly believed, the most favorable breeding-places for the 

 poison of yellow fever. In addition, statistics prove that, 

 in great cities subjected to ordinarily unfavorable condi- 

 tions, the denser the population, the sicklier and shorter 

 the lives of the inhabitants. Common sense and experi- 

 ence unite to teach that the denser a population, the more 

 wide- spread and frightful the havoc of communicable 

 diseases. 



Dr. Sternberg states that he fully believes that it is 

 practicable to put the city of Havana in such a sanitary 

 condition that it would be exempt from yellow fever. But 

 that this is an undertaking of considerable magnitude, in- 

 volving the expenditure of large sums of money, and re- 

 quiring much time, will be apparent when we have taken 

 account of the nature of the sanitary improvements ne- 

 cessary for the accomplishment of the desired result. 



Surgeon-General Weyman is equally positive that Ha- 

 vana may be rid of this disease, which is such a menace 

 to our country. England has driven it from permanent 

 occupation of Jamaica and other West Indian Islands, and 

 Mexico has excluded it from Vera Cruz, where, until the 

 past ten years, it had an even more tenacious hold than in 

 Havana. 



Yellow fever occurs more or less in all the denser cities 

 of the island ; in fact, in the cities of all the islands of the 



