656 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1913. 



but incidentally each such substitution helps to solve the smoke 

 problem. 



Another important factor is the electrification of railway termi- 

 nals. In Pittsburgh, for example, it is estimated that about one-third 

 of the total smoke now comes from locomotives. In Chicago the 

 proportion is perhaps even higher, and this element of the problem 

 has been so forcibly realized that the 28 railroads entering that city 

 are now contributing over $150,000 annually toward an investigation 

 conducted by the committee on smoke abatement and electrification 

 of the Chicago Association of Commerce to determine the practica- 

 bility of general electrification of the lines within the city in order to 

 eliminate this portion of Chicago's smoke nuisance. This probably 

 represents one of the most comprehensive engineering studies ever 

 undertaken along such lines, and is an inspiring illustration of 

 what may be accomplished by intelligently directed public interest. 

 With the growing strength of public opinion on these matters on the 

 one side and the rapid improvement of electric traction technique 

 on the other, it is perhaps not too much to hope that another decade 

 will see locomotive smoke practically eliminated from our larger 

 cities. 



To briefly sum it all up, the coal-smoke problem has grown to its 

 most aggTavated form from the centralizing tendencies of our civili- 

 zation, i. e., the concentration of life and industry in large cities, and 

 its solution has already begun and must for the most part be worked 

 out through still further developments of this same centralizing 

 tendency by which the direct use of fuels from which it is easily pos- 

 sible to produce smoke will be entirely taken out of the hands of the 

 individual and small operator and centralized in a relatively few 

 large establislxments operating economically under rigid smoke con- 

 trol, which in turn will supply the small consumer with heat and 

 motive power in such forms as gas, coke, steam, and electricity. The 

 key to such a solution is obviously well-directed, intelligent coopera- 

 tion between municipal authority, private capital, and the individual 

 citizen. 



The above covers, of course, only the smoKe due to imperfect com- 

 bustion of fuel, aside from which are many instances of smoke, fumes, 

 and dust arising from various industrial processes which can not be 

 merely " burnt up " into harmless, invisible gases simply by better 

 combustion. 



There are, on the one hand, certain true gases, most of them quite 

 invisible but still harmful to animal and plant life and sometimes 

 even to the very buildings of stone and iron ; and, on the other hand, 

 such visible clouds of dust or fumes as can be seen arising from chem- 

 ical and metallurgical works, cement mills, plaster factories, and the 

 like. 



