208 TUNNELING 



CHAPTER XIX. 



SUBMARINE TUNNELING (Continued); THE EAST 



RIVER GAS TUNNEL. VAN BUREN ST. 



TUNNEL, CHICAGO. 



THE East River gas tunnel is a notable example of a tunnel 

 begun in firm soil which unexpectedly developed treacherous 

 strata. It is also remarkable from the fact that the shield which 

 was employed to overcome the trouble was driven from rock 

 into soft material and from the soft material into rock again 

 with the utmost success. The following description of the 

 work is abstracted from a paper by Mr. Walton I. Aims, the 

 engineer in charge of the work, published in the Journal of 

 the Association of Engineering Societies for May, 1895, and in 

 Engineering News of July 11, 1895. The accompanying cuts 

 are reproduced from the last-named publication. 



During 1891 and 1892 the East River Gas Co., of Long 

 Island City, a corporation with works situated on the Long 

 Island shore of the East River, obtained from the New York 

 State Legislature a new charter, and such necessary legislation 

 as to permit the extension of their mains across the East River 

 into the city of New York. 



The feasibility of constructing a tunnel under the river 

 through which the gas mains might be laid was discussed, and 

 after some preliminary surveys and examinations a route was 

 decided upon from the works of the company at Ravenswood, 

 Long Island City, to between 70th and 71st Sts., New York, 

 passing under Blackwell's Island and the east and west chan- 

 nels of the East River. On about this line of location some 

 eight or ten pipe soundings were made in the two river chan- 





