The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

December, 1914 engines are assumed to work with a boiler pressure of 130 pounds per square inch, triple-expansion engines with 180 pounds, and quadruple-ex- pansion engines with 220 pounds per square inch. As regards the comparative weights, an advantage is proved in all cases. Some of the tabulated particulars in the paper may be summarized; in all cases the boilers are of the cylindrical type. The reduction in heating surface in the case of turbines is indication of the economy in steam consumption, which, of course, influences the total weight of machinery from boilers to engine tunnel. Notes on the German Navy Beyond the broad characteristics of displacement, speed and armament, little is known as to the internal arrangement and equipment of the newer vessels in the German navy. This is due to the extreme care which has been exercised in preventing leakage of information either from the Reichsmarine Amt or from the various naval construction works, im- perial and "private. It .-4s, . ofcourse, common knowledge that, apart from the three capital ships now going into com- mission or completing, there is a con- siderable gap in the forward movement of large vessels. For example, the list of battle cruisers cannot be extended until the Lutzow comes along, and this ship is very much in embryo, so much so that the Derfflinger may be regarded as completing the list of Germany's bat- tle cruisers, which number five in all. Of these--and there are now only four, the Goeben having bolted to the Black Sea and assumed the Turkish flag--the Derfflinger is the most' formidable, be- ing engined for about 100,000 steam horse power, and armed with eight 12- inch guns. She carries: in addition a heavy secondary battery, her displace- ment when fully loaded and equipped for action running up to approximately 29,000 tons. All the German _ battle cruisers now afloat are from the Ham- burg yard of the Messrs. Blohm & Voss, and the propelling machinery in each case consists of Parsons' turbines on four shafts. The plan employed is no doubt generally similar to the arrange- ment followed in the large four-shaft British battle cruisers--i. e¢., each pair of shafts, port and starboard sides re- spectively, are steamed in series, though possibly the German plan includes a connection whereby all the turbines can work in 'series on the lines adopted in the case of the Imperator, the Vater- land, and other vessels. The series of German battle cruisers Moltke, Goeben and Seydlitz have ten 11-inch guns, the displacement averaging THE MARINE REVIEW about 23,000 tons fully loaded. The Von der Tann has fewer big guns (eight in- stead of ten), and was the first of the large German battle cruisers. All these ships are very fast, and would be able to steam at speeds comparable with those obtained in the case of the large British battle cruisers recently completed. Of the German battleships, the Kaiser may be regarded as representing the most powerful vessel likely to lie in line against our own ships should a fleet action take place. The Kaiser has a displacement of about 24,500 tons, car- ries ten 12-inch guns, 14 5.9-inch guns, and is believed to be very heavily armored. The -speed of this ship is placed as high as 24 knots, and the ma- chinery consists of three-shaft turbines, high pressure and low pressure (with astern) turbines being arranged on each line. -The selection of the three-shaft plan (in preference to the four-shaft plan adopted in all turbine-driven British battleships) is doubtless due to the earlier German battleship arrangement of triple screws with reciprocating en- gines. The German navigating officers are accustomed to this system, though it has been said that a further season for its employment lies in the _ belief that with four-shafts the side wash is greater when steaming at maximum per- mitted speed through the Kiel Canal. The latest German battleship--the Kron- prinz, launched at Kiel in February of this year and now completing--is of the same general type, and is the last Ger- man battleship which will have 12-inch guns. Against the German battleships there are available the exceedingly formidable British vessels of the King George V class, as well as the larger battleships of generally similar type, such as H. M. S. Iron Duke. These have all ten 13,5- inch guns with a power ful secondary battery. In 'addition, they have the ereat vessels of the Queen Elizabeth class, one of which has already been commissioned. These are the fastest and most powerful battleships afloat, burn oil-fuel exclusively, and carry, as is well known, the new 15-inch guns. The British battleships are, of course, turbine-driven, and have the four-shaft arrangement, each pair of shafts (port and starboard) working in series, a method which, since the days of the Dreadnought, has given every satisfac- tion. The boilers in the large German war- ships are mostly of the Thornycroft- Schulz type, though in the newer battle cruisers it is likely that the boilers are similar to those fitted in the Hamburg- Amerika liners Imperator and Vater- land. Many engineers will be wonder- ing how the boilers in the German high seas fleet are getting on, since with the 465 crowded engine-rooms which are char- acteristic of German naval practice, the evaporators will likely be cut down to an extent far below what is usual in the British navy. In warships, where the boilers are of the watertube type and the load rapidly fluctuates within wide limits, the condition of the feed water is of supreme importance. In filtration of salt --whether from condenser tube ends or from a priming evaporator--is danger- ous, and may, indeed, prove disastrous, since if salt water gets into the boiler trouble ensues immediately, and with turbine machinery, as with other pro- pelling engines, priming boilers are ~ anathema. No doubt one of the limitations of the German naval designers has arisen from the need to curtail the different types of ships and divide the vessels into fewer specific classes, each class being earmarked for a wider range of duties than the corresponding British ships. In the British navy specialisation has been developed to a high pitch, and, though this invelves more ships, it also 'brings about a state of great flexibility when the time comes to distribute fleets for action. The German engine-rooms are accordingly more crowded, ship for ship, than are the British; and for given displacement, speed and armament the stress on the German machinery-- particularly the auxiliary machinery--is greater. All this reacts upon the con- ditions obtaining in the case of a fleet which, like the German fleet at the pres- ent time, is lying dormant, and the pro- cess of deterioration has quite a direct influence upon eventual mobility. A further circumstance which assists notably in the performance of the heavy task which falls now upon the British navy lies in the possession of a large number of fast armored ships driven by reciprocating engines. At low powers these vessels are relatively economical, while at the same time they can be pushed up to a compara- tively high speed. Among ships of this class may be mentioned the Drake, King Alfred, and Leviathan which are ar- mored cruisers of about 14,500 tons dis- placement, with twin-screw triple ex- - pansion (four-crank) engines, indicating up to about 31,000 horse power. A further technical point which is not without significance relates to the coals used in the two fleets. The British navy has behind it inexhaustible supplies of the finest steam coal, and with moderate rates of combustion the uptake condi- tions are, for warships, quite good. The German coal margin is different, and is believed to comprise fuel running rela- tively high in ash, and distinctly smoky when worked at large rates of combus- tion. This is a matter of definite im- portance.--Fairplay, London.