Biggest Cast-iron Pipes in the World 



THE big gas-mains in the Astoria- 

 Bronx Tunnel at New York are 

 probably the largest cast-iron pipes 

 ever made. The internal diameter is six 

 feet; the thickness of metal is two and 

 three-quarter 

 inches; and the 

 length twelve 

 feet. The one 

 end has the or- 

 d i n a r y bell 

 form; the other 

 the spigot. The 

 weight of one 

 length is about 

 twenty-six 

 thousand 

 pounds. 



These mains 

 are laid parallel 

 and run down 

 a shaft at As- 

 toria on Long 

 Island, along a 

 tunnel two 

 hundred and 

 twenty-five 

 feet below the 

 surface, under 

 East River, 

 and then up a 

 second shaft 

 at One Hun- 

 d r e d and 

 Thirty-second 

 Street and 

 East River. 

 They are to car- 

 ry gas into the 

 Bronx, the most 

 rapidly grow- 

 ing borough of 

 New York city. 



It is not an impossibility that the 

 tunnel may sometime be flooded with 



A row of seventy-two-inch pipes for the Astoria 



line, New York city. In the foreground is a spigot 



joint with tee cut-off 



water. Under such circumstances it 

 would not be desirable to have the long 

 lines of iron tubes begin to float. 

 While the pipes are heavy enough to 

 prevent their floating, the margin is not 



grea t . The 

 weight of 

 water dis- 

 placed by a 

 cylinder 

 twelve feet 

 long and 

 seventy-seven 

 and one-half 

 inches in 

 diameter is 

 between 

 twenty-four 

 thousand and 

 t w e n t y - f i V e 

 thousand 

 pounds. The 

 overlap where 

 bell-end en- 

 compasses 

 spigot-end 

 complicates 

 the matter a 

 little, but after 

 all allowances 

 are made, there 

 would prob- 

 ably be a good 

 solid weight to 

 the pipe lines if 

 the tunnel were 

 full of water. 

 The amount 

 of lead used 

 to calk the 

 joints is about 

 two hundred 

 and twenty- 

 The mains rest 

 on concrete saddles set six feet apart. 



The small motor is driving eight steel knives which 

 are cutting the pipe from the inside 



five pounds per joint. 



200,000! 



In just eight months this magazine has doubled in circulation — it has 

 grown from 100,000 to 200,000 copies. 



Tell your friends to read the Popular Science Monthly. Tell them 

 that the Popular Science Monthly gives all the news of invention and 

 science, and that it is easy to read and full of pictures. 



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