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THE NATIONAL GEOGRAPHIC MAGAZINE 



The method of treating the sewage at 

 the disposal plant consists of hydrolitic 

 tanks, sludge-digesting tanks under still 

 water, stone sprinkling filters at a lower 

 level, consisting of beds of broken stone 

 &y 2 feet deep, over which the sewage is 

 distributed by means of sprays, then by 

 under drains is carried to settling basins 

 at a still lower level, and thence into 

 Back River, coming out practically pure 

 water. 



Between the settling basins and the 

 river into which the effluent is discharged 

 there is a fall, which is utilized to gen- 

 erate electricity used to run pumps and 

 other machinery for various uses 

 throughout the plant. 



Baltimore, in one respect, reminds one 

 of Rome, the City of Hills, and in an- 

 other respect it reminds one of Pompeii 

 as she lay looking out over her beautiful 

 bay under a mild climate, the people 

 coming and going. When the attention 

 of the citizens of Pompeii was called to 

 the dangers of smoking Vesuvius near 

 by, the answer would be : "It has never 

 given us any trouble, so why should we 

 worry ?" 



Just as the attention of the people of 

 Baltimore has been called to the lack of 

 sanitation, the reply has been : "It has 

 never given us any trouble ; why should 

 we worry?" The Pompeiians were not 

 as smart as the Baltimoreans — they did 

 not awaken to a realization of their dan- 

 ger until too late, while the Baltimoreans 

 have risen to the occasion by preparing 

 before an epidemic should compel them 

 to do so. The people of Baltimore have 

 been sleeping and working over a volcano 

 which, if once started, would make the 

 city stand out before the world in a man- 

 ner similar to that of 1904; but in the 

 place of fire it would be epidemic. 



Beneath the surface there is an under- 

 ground air which investigation has 

 proved is almost as ceaseless in motion as 

 that in which we move. Whenever the 

 ground becomes heated it streams out 

 through the myriad pores of the earth's 

 surface into the sunshine ; when the 

 ground cools, back through these pores 

 rushes the aerial air. Every wind that 



sweeps the surface moves the air beneath 

 in great volumes. With every rain it is 

 driven deeper down. The movement of 

 this buried atmosphere is slow, because 

 it must find its way around myriads of 

 soil particles which block its path, but it 

 is of great extent and importance. 



It is reasonable to suppose that with 

 thousands of septic tanks filtering into 

 the subsoil of a city for years and years 

 this under-ground air would, in the 

 course of time, grow foul. Each year this 

 would grow worse and worse, until there 

 would be a breaking point. 



The men who were far-sighted enough 

 to rouse the people of Baltimore from 

 their slumbers and begin this great work 

 before it was started in another way de- 

 serve a monument to their memory. I 

 do not know of a single instance in his- 

 tory where a city the size of Baltimore 

 has at one single stroke attempted to 

 sewer the entire city, treating its enor- 

 mous sewage by the most modern meth- 

 ods, both as to disposal of its storm water 

 and purifying its sewage almost to drink- 

 ing water. 



In the sewerage system being con- 

 structed in Baltimore every known latest 

 improvement is being used, besides nu- 

 merous improvements which have been 

 designed by the engineers of the com- 

 mission. 



One of the greatest difficulties encoun- 

 tered has been the vast number of un- 

 der-ground obstructions beneath the 

 streets of the city. 



In a recent address made to the Society 

 of Civil Engineers in Washington, D. C. r 

 I stated that the sewage problem as a 

 world factor is forcing itself to the front 

 very rapidly, and our country is ap- 

 proaching a point where it will have to 

 deal with the sewage question on a broad 

 scale. As rivers run from one state to 

 another, the states cannot deal with the 

 problem without clashing, and it will 

 soon have to create a National Sewage 

 Board similar to those abroad. 



We have heretofore, on account of the 

 vastness of our country and the size of 

 our rivers, simply disposed of the sewage 

 in the most economical manner at the 



