Popular Science Monthly 



901 



J 



Pittsburgh on a smoky day. The Mellon Institute investigations showed that smoke had a 

 depressing effect upon the minds of many people. It also had a marked effect on health 



the annual deposit during 1910-11 was 820 

 tons per square mile. 



In Great Britain the recently formed 

 Committee for the Investigation of Atmos- 

 pheric Pollution has installed standard 

 measuring apparatus in sixteen English and 

 Scotch towns. In some cases there are as 

 many as ten stations in a single town. The 

 organization is analogous to a meteorologi- 

 cal service, with its network of stations for 

 observing the weather. The standard 

 collector, or "pollution gage," consists of a 

 large cast-iron funnel, enameled on the 



inside, having a collecting area of four 

 square feet. Projecting above the gage is a 

 wire screen, open at the top, intended to 

 prevent birds from settling on the edge of 

 the vessel. The gage communicates at the 

 bottom by a tube with one or more bottles 

 for collecting rain-water, with its solid 

 contents. The bottles are emptied once a 

 month and their contents analyzed. Thus 

 information is obtained not only as to the 

 total monthly deposit of soot and dust, but 

 as to its chemical composition. The intens- 

 ity of sunlight is also measured. 



The same view as above, photograpiu<i wncn Pittsburgh was rid of the smoke evil. The city 

 now saves more than a million dollars annually on its lighting, laundiy, and cleaning bills 



