419 



iji isolation in tlie country. Many conditions are so extreme tliat the 

 reader lias no ditliculty in deterniinin.i,' wliere a mention a])plies : pnre 

 food, contaminated food; .t,'ii(id water, polluted water; pure air, impnre 

 air; smog clonds overliead, lilue sIvy overliead. 



Crowding, food, water liave all for a long time I'eceived attention and 

 great efforts have been made to improve conditions. lUit not nntil re- 

 cently have air conditions been given attention. Black smoke clouds re- 

 ceive f refluent mention in the public press. The dust problem is likewise 

 receiving moi'e and more attention — if the people knew to what extent it 

 is a factor in jtroducing ill health aud disease and death they would soon 

 make a determined effort to alter existing conditions. 



What are the effects on a pnre air man when he goes into the large 

 and dirty city overhung with smog clouds? Dust makes him feel dirty, 

 his hands and clothing are soiled; he "blows blacli" into his handlier- 

 chief and spits black ; there is more or less free production of mucus, 

 followed perhaps by pus formation, and he will speak of having catarrli ; 

 in attempting to liawlv up morning phlegm he may become nauseated and 

 even vomit ; dust particles reach his lungs and become imbedded, the lung 

 becomes black (in old city residents it is coal black, pneumokoniosis) ; 

 he experiences all sorts of disagreeable sensations, symptoms of ill health 

 so-called, symptoms shade oft" into aft'ections, minor maladies and disease; 

 infective particles are locked up in tlie lymphatics, forming "kernels" in 

 the neck and tumors along the windpipe and in the lungs and these burst- 

 ing pro<luce disease and death. The two great dust diseases are tuber- 

 culosis and pneumonia, they decimate mankind by thousands and millions. 



Medical men have names for tlie eft'ects produced by the inhalntinn 

 of different forms of dust: Anthracosis for the effects produced especially 

 ill coal miners ; Byssiuosis due to inhaling cotton dust, as in cotton fac- 

 tories : Clialicosis, Silicosis and Siderosis are names applied to affections 

 in potters, stone masons and iron wo rivers who inhale gritty matter. Tlie 

 term Pollenosis is expressive and should come into general use; the name 

 indicates a state or condition produced by inhaling pollen, that is in those 

 susceptible. 



Kinds of Dust\ — There are all kinds of dust, all of varying impor- 

 tance in the welfare of man. To the physicist dust is of great importance 

 in the matter of light and shade and precipitation ; to tlie tidy house- 



1 For a synoptical table of Kinds of Dust an relationship to stages of civiliza- 

 tion, see my Presidential Address, Indiana Academy of Science, for 1906, p. 23. 



1 



