MECHANICS AND USEFUL AETS. 27 



alone. Besides, the 3,000 ships that now annually enter the harbors of Calais, 

 Boulogne, and Dunkirk, with a tonnage of 40,000 tons, will, of course, yield 

 a great portion of their traffic to this railway, which will be safe, expeditious, 

 and comparatively inexpensive. 



Engineers are at present engaged making surveys and soundings for the 

 purpose of estimating, as accurately as possible, the utmost cost, and con- 

 tractors, offering guarantees of responsibility, are ready ta take work. 

 The following is the conclusion of a recent report on the subject : 

 "In conclusion, we are impressed with the conviction that we have proved, 

 not only that this project is possible, but that it will be comparatively easy to 

 construct a railway under the Channel. "We have now developed our system 

 of maritime 'wells,' which would divide the subterranean tunnel into differ- 

 ent sections. Our plan of a double vault would give as ample securities as 

 any of the ordinary railways possess. The tunnel would set aside the arm 

 of the sea which separates France from England. It would bind, upon the 

 most solid foundation, the Continent with Great Britain, which is at present 

 isolated from the rest of Europe. Our project has been received every where 

 with the most lively sympathies, and an Anglo-French Company will be im- 

 mediately organized upon the most powerful basis to execute the railway of 

 Calais." 



NEW METHOD OF REPAIRING A SHIP WITHOUT DOCKING. 



The immense British screw steamer, Himalaya, having become seriously 

 damaged in the Black Sea, it became requisite that repairs should be made at 

 Malta. There being no dry-dock at the place of sufficient capacity to receive 

 her, this difficulty was surmounted in the following manner : The Himalaya 

 is an iron vessel, constructed on the life-boat principle, with water-tight com- 

 partments. She was taken into the dock about noon, and water introduced 

 into her fore compartment with syphons, for about two hours. At that time 

 a powerful purchase was fixed aft to four derricks, and hove taut, when she 

 started up 18 inches. Three hours later the purchase was hove again, when 

 she moved up 12 inches, and so continued until half past eleven p. M., when 

 it was found that the shaft-hole of the propeller was 15 inches out of water. 

 At this time her immersion was 7 feet 10 inches aft, and 27 feet forward, with 

 about two feet of water under her forefoot ; and this was accomplished so 

 easy that persons witnessing the operation almost doubted then- own eyes. 

 She strained nothing whatever, and when her defects had been made good, 

 she was let down, the water in her fore-compartment pumped out, and in 12 

 hours she regained her natural position. It will be seen that she was water- 

 borne the whole time, and that by destroying the buoyancy forward the as- 

 sistance she required aft to raise her was comparatively small. This opera- 

 tion, probably, would answer only for an iron vessel, inasmuch as any wooden 

 vessel, as ordinarily constructed, would be found deficient in longitudinal 

 strength. 



The Nautical Magazine, in this connection, also recalls to remembrance an 

 ingenious plan adopted some years since, at the Navy Yard at Norfolk, for 



