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322 torpedoes 7.1 per cent of her merchant ships; 14.1 per cent are held by the enemy and are being made the most complete use of; 43 per cent are in the ports of the United States, Cuba, Pa- nama, and neutral countries, and 35.8 per cent are still at home. American consuls who have come here from Germany reported that the stories of tremendous activity in German ship yards have been exaggerated. They as- serted that the ship building industry in british HE Woolston Shipbuilding es- I tablishment of Messrs. John I. Thornycroft & Co., England, built two paddle tugs to the order of the British admiralty, and are now in service at the Sheerness dockyard. As the conditions in which these vessels are required to operate are somewhat exceptional, the paddle has been preferred to the screw system. At Sheerness the tide runs at springs up to as much as 3% knots, and, not only are the largest dreadnoughts to be moved, but there is a_ limited amount of room in which to maneu- ver, for there is a line of moorings up each side of thé river with a mini- mum intervening space. It is mainly for these reasons, and in view of the fact that the duty lies in enclosed waters and that the tugs in question will not be required for ocean-going work, that the paddle has been pre- ferred to the screw tug, as it has been found that the former obtains immediately a more solid grip of the water and there is considerable slip with a screw propeller when there is no way on. These two tugs, named the Sturdy and Strenuous, are of the same general design and dimensions, the measurements being as follows: Length between perpendiculars, 145 feet; breadth, molded, 28 feet; depth, molded, 15 feet; draught, extreme, 11 feet; speed, 12% knots. The bridge deck extends about 50 feet forward and aft and right across the paddle-boxes, and here are situ- ated the wheel and chart house, the wheel being connected to the bow McLachland steam steering gear on the main deck just forward of the engines. On each side of the bridge is a pair of Chadburn improved tele- graphs, as fitted to so many British warships. In these Chadburn instru- ments the lever is in the form of a crank handle, one complete revolu- tion of which is required for each sep- arate order. For instance, to go full ahead, three revolutions of the crank handle in the ahead direction are required; thus the motion is an easy one for the body. The ahead move- THE MARINE REVIEW Germany, so far as merchant vessels are concerned, has been stagnant since the first year of the war. There have ap- peared in many German newspapers and trade journals, they said, very optimistic accounts of the tonnage being turned out from German yards, but these accounts mostly represent what was desired to be done and what was projected rather than what was actually being accom- plished. Facing the prospect, a wholly inade- dmiralty Orders ment is the natural one if the boat is required to go ahead, and, further- more, there is no question of looking at the dial to see if the pointer is resting at “half” or “full” or between the two; the complete’ revolution makes it quite definite. To go astern, the crank handle has to be brought round backwards, again the natural movement. The only objection which can be offered to such an arrange- ment is that seven turns have to be made for full ahead to full astern, so that it is a little slower than the ordi- nary form. However, as when steaming about 10 knots against a tide of 1% knots, the ship stops in very little more than her own length from the time the tele- graph is first moved; there is proba- bly not much in this. At each end of the dial is an additional space “couple” and “uncouple”’, so that when settled down for a long tow the two pairs of engines may be connected together, and when so connected only one telegraph is used. The connec- tion from the bridge to the engine room is by shafts and bevel wheels, and, as there are no chains, the gear- ing will outlast the ship herself as far as wear and tear are concerned. The arrangement of the boiler aft of the engines necessitates the towing hook being placed rather further aft than is generally the case with a screw tug. On the foremast is fitted a big derrick capable of lifting 5 tons, ‘the power being obtained from the Clarke-Chapman steam winch forward. Aft, again, there is a steam capstan for handling heavy tow ropes and for warping. Forward under the main deck are the crew’s quarters, 40 men being berthed on lockers and in hammocks, the officers having sepa- rate cabins aft. The machinery consists of two sets of diagonal compound condensing en- gines with cylinders 22 inches and 40 inches diameter by 60-inch stroke, and giving a combined horsepower of approximately 1,250. Each pair of engines forms a complete unit, with its own independent condenser and September, 1917 quate amount of tonnage presents to her as a post-bellum problem, Germany is confronted also by the cold fact that English ship yards are working at ca- pacity on merchant bottoms and are turning out vessels at the rate of 1,000,- 000 tons a year. The American yards have not yet reached capacity, but when they do, and it is hoped they will within a very few months, they are expected to match the output which has been at- tained by the British. Yaay / : iT al e UuULsS air circulating and feed pumps. The two shafts can, however, both be con- ISSSY9 nected together by a dog clutch, which | can be inserted, even when the en- gines are running at full speed of 40 revolutions per minute by means of a hand wheel and screw. This engagement is effected at speed with- out the least difficulty. When in the river and maneuvering the engines work independently, but when at sea they always work together to prevent racing. There is a very close equal- ity in the horsepower developed by each pair of engines, the difference being considerably less than 1 per cent, though there has been a good deal of difference between the high- pressure and low-pressure cylinders in each case. Ordinary double link gear is fitted, each set of gear hav- ing its own two-cylinder “all-round” reversing engine, the connection be- tween the way shaft and the reversing engine being worm gearing. The two cylinders form a very quick acting and positive reversing gear. The main engines have piston valves on the high-pressure cylinders and flat trick valves with relief frames on the low-pressure cylinders. The frame- work of the main engine is of some- what unusual form, the only castings being comparatively small parts for the main bearings, and these are of mild steel, the rest of the framework being entirely of forged steel. The columns are used as crosshead guides, being squared for the purpose, the central one taking one of the slippers of each of the cylinders. For this purpose it is, of course, widened out on the surface, but is grooved out along the sides in order to save weight. The water service is on an elaborate scale and is supplied from tanks filled by a branch from the fire main. Fine save-alls are fitted under the cranks and guides, which should lead to an economy in oil and con- tribute to a cleanly engine room. There are two big fire and salvage pumps delivering 120 tons per hour each below deck, and, of course, the usual filters, feed heaters, etc., to-