256 ATMOSPHERE IN RELATION TO HUMAN LIFE AND HEALTH. 



The mortality of the British army in barracks from consumption in 

 the ten years 1837 to 1846 was 11.9 per thousand. After the report of 

 a royal commission in 1858, ventilation aud air space were greatly 

 extended, and the mortality immediately and rapidly fell 5 in 1888 the 

 consumption rate was only 1.2 per thousand. 



The disease prevails more on wet, cold, clayey ground aud damp places 

 generally than on high and dry sites, and all causes of chills and colds 

 give an opportunity to the infection of the specific bacilli where they 

 are present in sufficient numbers and strength. 



Cold countries are rather less subject to the disease than temperate 

 and warm climates, but everywhere the most important factors are the 

 habits of the people. A moist atmosphere, with wide daily range of tem- 

 perature, favors its prevalence. In Greenland, Labrador, Iceland, Spitz- 

 bergen, NovaZembia, Finland, Siberia, and the northern parts of North 

 America the disease has been rare; also especially on mountain ranges, 

 high plateaus, and little-visited districts, such as the Soudan. In 

 Algeria the nomad Arabs were free from it. The Bedouins who 

 exchange their tents for stone-built houses suffer to some extent. 

 Many uncivilized tribes are exempt until they adopt the clothes and 

 way of living of civilization. Outdoor life in the free air, and clean, 

 spacious sleeping quarters almost or quite annihilate consumption if 

 animal sources are excluded. Soldiers on campaign, fishermen, hunters, 

 engine drivers, gardeners, and farm laborers are least attacked ; workers 

 in gritty stone or metallic dust, in hot, close, crowded, and damp 

 rooms or factories or mines, and dwellers in damp houses, back-to-back 

 houses, and close courts furnish the largest numbei of victims. In 

 the old town of Havre, with its airless, narrow streets, the mortality is 

 three times as great as in other x>arts of the town. 



It has been shown that in proportion as a population, male and female, 

 is drawn to indoor occupations, the death rate from consumption 

 increases. 



An elaborate investigation for official purposes by Dr. Ogle showed 

 the mortality from phthisis and lung diseases of men from 45 to 65 

 years of age working in pure aud vitiated air in England, to be as fol- 

 lows: 





Phthisis. 



Other 

 lung dis- 

 eases. 



Total, 



Pure air : 



55 

 52 

 61 

 62 



84 

 152 



144 

 233 



45 



50 

 56 



79 



59 

 65 



94 



84 



100 





102 





117 





141 



Coiifiiied air: 



143 





217 



Highly vitiated air: 



238 





317 







