COMPRICSSKI) AIK IMIKNOMENA. II3 



Care is taken nowadays that pure air is drawn into the 

 compressors to be discharged below. Formerly there was great 

 carelessness in this respect, the air being drawn from the 

 engine room frequently, and containing dust and impurities. 

 The air should be taken from out of doors and at some height 

 above the streets. 



Among the man}- nationalities working upon the New 

 York tunnels, the Negro and vSlav are most frequently to be 

 found, and they show great physical stamina and adaptability 

 to the work. The Italian is very rarely found working in 

 compressed air. This may be owing to the fact that the life 

 necessitates the consumption of much nutritious food and 

 increased expense of living, which he is unwilling to incur, 

 even for the increased pay, or it may be that his livelier imag- 

 ination invests the mysterious medium with exaggerated 

 terrors. 



Through the many tunnels under New York waters there 

 will be passing daily and nightly an enormous stream of 

 travel, for within a radius of twenty-five miles of the City 

 Hall the population is now between five and six millions, and 

 growing at a rate which no other great city has ever equalled. 

 In affording transit facilities to this focus of the United States, 

 the machinery and material would have availed nothing, had 

 not " the air " served as a dam and wall of defence against 

 the undermined rivers, to the workers beneath the river bed. 



