Popular Science Monthly 



327 



In the illustration below may be 

 seen one of the many trestles 

 which carry gaspipes across a 

 torn-up street. After one serious 

 explosion, New York put these 

 pipes in the air where leaking gas 

 would escape without danger of a 

 catastrophe. The average cost 

 of doing this is twenty-five hun- 

 dred dollars; and where larger 

 distribution mains must be han- 

 dled, the cost runs as high as ten 

 or eleven thousand dollars 



