The Submarine Torpedo Boat
Its Characteristics And Modern Development

22 THE SUBMARINE TORPEDO BOAT field has secured less efficient results than any other nation. Germany did not take up the development of submarines until rather late, but characteristic of this nation, having once decided to go into the field, a sufficient sum of money was at once appropriated to meet the expenses and the Krupps were given the commission to undertake the prob- lem of development. The Germans have also tried out the d’Quevilley type, a French product, but with what success is not known; however, as the French had experi- mented for some years with this type and had gained no apparent success it is doubtful that the Germans have done anything more. The essential feature of the d’Quevilley boat is the single unit power system, using the steam en- gine. The steam for submerged propulsion is generated by means of a soda boiler; the principle of the system being to utilize heat in the form of steam generated by a slaking process as is demonstrated in the slaking of lime. This principle is not new however, having been tried out in this country in 1885 by Prof. J. H. L. Tuck on his sub- marine boat Peacemaker. Going into the field comparatively late, as Germany did, she was enabled to profit to a considerable extent by the experiences of the other countries. The boats U-9 to U-16, which have taken such a promi- nent part in the submarine activities off the English Coast, have an extreme length of 142 feet, a moulded breadth of 12 feet 4 inches and a mean draught in the surface condi- tion of 9 feet 8 inches. They have a submerged displace- ment of about 300 tons and a surface displacement of 235 tons. These vessels are all of the submersible double- hull type of construction with a cigar shaped inner hull