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272 ject are due primarily to William Froude, the originator of modern experiments, which have been the most useful appliance of research in this line one could imagine. The law of comparison by which, from the resistance of a small model at low speed, we can closely estimate the resistance of a large ship at high speed, is commonly called by naval architects Froude’s Law. It appears to have been originated independently by Mr. Froude, although as a matter of fact it is a particular case of the general law of mechanical similitude, apparently first enunciated by New- ton. How Ship Resistance is Found The resistance of ships by the Froude methods is regarded as made up of three elements: The friction of the surface, which, for low-speed vessels, may be as much as 90 per cent of the total, and seldom falls below 50 per cent, even for very fast vessels; the wave-making resistance, due to the energy required to create and maintain a system of waves ac- companying the motion of the ship through the water; and the eddy re- sistance, due mainly to eddies behind stern-posts, struts and other append- ages, and hence quite a small factor in the total. The law of comparison applies with great accuracy to the wave-making resistance, and with reasonable accuracy to eddy resist- ance. To frictional resistance it is not applicable, but Mr. Froude, by experiments on _ surfaces, established coefficients of frictional resistance which are used to this day, although for some time naval architects have felt that it would be desirable to revise these coefficients upon the basis of experiments on a large scale. The procedure we use at the present time in obtaining the lines for a ship is about as follows: By the use of tables and curves which have been produced as the re- sult of years of experiment at the Washington model basin, certain co- efficients, representing a form of under-water body, are selected, as giving a close approximation to the best solution of the particular prob- lem in hand. By the use of these co- efficients we can arrive at approxima- tion to the best dimensions for any particular ship, and by the further use of certain standard forms ’ of waterlines can draw, with little dif- ficulty, the lines of the vessel. From the same data we can obtain a close approximation to the resistance, at varying speeds, of a hull built from these lines. These steps permit of settling the broad general character- istics of the design. The lines so THE MARINE REVIEW drawn are then sent to the model basin, where a model to exact scale is built and its resistance accurately measured at varying speeds. In im- portant designs, as in the case of the battle cruiser, this model will receive many variations in shape and refine- ments of details until it appears probable that the minimum resistance for such a hull has been reached. The resistance curve obtained from ‘the final model is then used as the basis of the design of the machinery plant and propellers for the vessel. There are, of course, many other divisions and subdivisions of naval Built Our Men-of- War “During the years Admiral Tay- lor had charge of the model basin he by no means confined his atten- tion to the theoretical aspects of naval architecture, but he was also the principal adviser to the chief constructor of the navy on all mat- ters pertaining to the design of every vessel of importance on the navy list. It was in this capacity that he conceived what is now known as the American or center- line arrangement of gun turrets on the Dreadnought or big-gun type battleships built for the American navy, and which has since been adopted by every great naval power. “In December, 1914, he was ap-— pointed, by the President, chief con- structor of the United States navy, with the rank of rear admiral, and chief of the bureau of construction and repair. In this capacity he has ‘been responsible for the design and building of the ships in the huge naval program provided for during the last two years. “At this time, when our country’s safety and success in the great war debends so largely upon a powerful and efficient navy, I deem tt a spe- cial honor and privilege to present as Franklin medallist a man who has played a foremost part in its development, and whg is conceded to be the greatest living naval archi- tect and naval constructor, Admiral David. Watson Taylor.’—From the presentation address. architecture which enable us to fore- tell with a considerable degree of accuracy the behavior of a_ vessel under the many different conditions which may be met in a varied career of service, as, for instance, the de- gree of punishment which a ship can stand before sinking, when subjected to attack by gunfire, submarine tor- pedo, and mine. and aerial bomb. These are factors which hitherto the naval architect has not been required to consider as regards merchant ships. If present piratical methods of war at sea are to continue, the distinction between merchant and war _ vessels will necessarily disappear. — As regards vessels of war, experi- August, 1917 ence to date has shown broadly that the science of naval architecture has provided ships which function as an- ticipated. The enormously destructive weapons of the day are able to de- stroy in time anything that floats, and without disparaging Mahan’s dictum that “Good men in poor ships have always won over poor men in good. ships’, there is no doubt that good ships are essential even to the best men. Our ships are now to undergo the “trial by ordeal’ of the features carefully and patiently planned in past years. May they prove. worthy of the good men that man them! There is one final thought, however, which naval archi- tects the world over feel today. The progress of late years, which has seemed rapid, will seem slow indeed by the side of the progress and de- velopment which must and will be made during the years just ahead of us. The science of naval architecture, whether applied to vessels of war or peace, has a weighty part to play as the world undertakes to meet the changed conditions of war time and of the time after the war. Use Lake Boats Along Coast in Winter Various steamboat and shipping inter- ests in Chicago are considering a plan to send some lake vessels to the coast for service during the winter months. The men who are fostering this scheme point out that these boats could be used to excellent advantage in the eastern coast shipping trade from November to April, when navigation on the Great Lakes is closed. Although the cost of refitting the boats for salt water service would, it is estimated, average about $5 per horsepower, the backers of the plan be- lieve that with governmental co-opera- tion, the plan will be entirely feasible. The originators of this idea believe that it will be possible to make arrangements with the government whereby the initial cost of replacing equipment will be borne by the government—the ship owners re- paying the government from the profits earned during the five months when the boats are in service along the eastern coast. Laden with lumber for China, the motor ‘schooner MaArGARET, on_ her maiden voyage from the Columbia river, sustained some damage from fire while off the Oregon coast. The vessel was towed ‘back for repairs. The fire is reported to have been caused by a broken circuit in one of the engine room switchboards. The after part of the ship was gutted by the flames.