GERMAN SUBMARINES IN PARTICULAR. 117 



They carried 4 bow tubes, 2 stern tubes and 19 torpedoes. They had a designed 

 surface speed of 15.8 knots and a designed submerged speed of J."] knots. Only 

 four of these boats were actually completed at ihe time of the armistice, but there 

 were a large number under construction in various parts of Germany. 



A. — It is not the purpose of this paper to attempt to cover the entire question of 

 German submarines, but the following notes on features of the design of these ves- 

 sels are enumerated : — 



These points are selected more on account of minor variations from other 

 standard practices than from their relative importance as regards design. 



Frames are numbered from aft forward. 



Frames of inner and outer hulls are numbered independently from aft forward, 

 so there are two systems of framing and two sets of numbers. 



The hull frames, so far as noted, are the same size above and below the deck 

 level. Stiffening is obtained in way of decks, flats, bulkheads, etc., by means of 

 light brackets at decks and heavier brackets at bulkheads. In a few instances some in- 

 creases in depth of angle bulb frames to suit local conditions were noted. 



The superstructure plating is galvanized, as are also the superstructure frames 

 and beams. The plating varies from 5 pounds to 10 pounds, depending on location; 

 this also varies in different boats. 



Three sets of draught figures are secured to the outer hull, one set forward, 

 one set aft, and one set amidships. These are spaced 10 cm. apart. 



No battery lining was noted in any boats. The battery tanks are given the 

 ordinary red lead coats, and over this is a bituminous solution or graphite paint — 

 some form of acid-resisting paint. Either they have little or no acid spilled or they 

 flush the tanks with some anti-acid solution, as there was evidence of the acid-proof 

 paint being rubbed off in various places. There was no evidence of acid spilling. 

 The writer was informed at Kiel that they flush out tanks with soda solution. 



Various kinds of deck-covering paint were noted on top of the superstructure, 

 including bituminous solution and sand, similar to U. S. Navy efforts on destroyers 

 and submarines. 



Only one anchor is fitted. This is a patent deck anchor fitted in a housing hawse 

 pipe on the starboard bow. The shank houses in a tube casting, and the crown and 

 flukes project slightly beyond the ship's side. The hull is recessed to house all but 

 a few inches of crown and flukes. A guard, like a destroyer propeller guard, is 

 fitted around the anchor. The weight of the anchor on the U-124 (1,200-ton boat) 

 is 700 kg. (1,520 pounds), and it appears that the weights of anchors are about 125 

 pounds per 100 tons of boat. U-71-80 have no deck anchor but one mushroom 

 anchor instead. No other boats of recent type have a mushroom anchor. The 

 mushroom anchor of old UC-boat weighs about 660 pounds. 



No armor, as such, is fitted on any of the boats except the U-140, which has 

 a I -inch armor envelope around the conning-tower. The top strake of the inner 

 hull is 1 inch thick on 11-139-142 and ^ inch on U-135, but only ^4 inch to % inch 

 on U boats and ^ inch to Yz inch on the UB and UC boats. The conning-tower 



