would be still further simplified if there were two separate 

 bridges for a double track. He calculated upon the train being 

 drawn through the tunnel by electricity, in the same manner 

 as in the case of the London Subway, or by compressed air. 

 Smokeless locomotives were in use in other tunnels ; in this 

 way tunnels were infinitely more easily kept ventilated. With 

 regard to corrosion, it was a question which always presented 

 many difficulties to marine engineers. However, if the steel 

 of the bridge were perfectly covered in the way he had 

 described with Portland cement, there would be no danger of 

 its corroding. He knew instances where iron that had been 

 coated with this cement was as good to-day as it was twenty 

 years ago. Then as to deep anchorages; as the anchorage was 

 particularly good inshore he expected that it would be the 

 same in deep water, as the bottom right across was similar 

 He had been so informed by authorities. In conclusion, he 

 thanked the audience for having so attentively listened to him, 

 and the gentlemen who had offered criticisms on his paper. 



Had he been reading the paper before a body of experts pure 

 and simple he would have gone minutely into the more 

 scientifac problems involved in such a structure ; but having 

 been requested to prepare the paper in a popular form he had 

 endeavoured to omit the too technical subjects referred to 

 by some of the speakers. 



Since this paper was read I observe that Sir E. J. Reed, M.P., has lodged a Provisional 

 Specification of a patent for submerged bridges to connect railways, and in a recent 

 issue of the Contract Journal, it is stated that a well known scientific M.P. is now busily 

 engaged designing a Submerged Bridge for railway connection between England and 

 France, at the instigation of Sir Edward Watkin, M.P. — J. M. 



C% 1 



