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TAE MARINE. REVIEW 23 Naval Architects, of 1903, page 190: "When the launch is light, drawing 11 inches, with the same power the speed is increased from 9.2 miles an hour with the flap down to 1o miles an hour with the flap up; and when the draught is 28 inches, loaded with 20 tons, the speed is in- creased from 6.9 miles an hour with the flap down to 8.25 miles an hour with flap up, the power at both speeds being the same. As might be expected, the increase of efficiency due to the lifting of the fan is greater when the boat is loaded, the lower speed in each case being what it would have been if there had been no adjustable flap, clearly showing the advantage of the flap." Is not this an admis- sion that the vessel would be better without the flap, meaning the same as the expression that "a dead Indian is the best Indian?" Then why should there be a flap if the boat does better with it raised? Why should it be employed to make the tunnel longer, thereby decreasing the displacement and with it increasing skin resistance? It is also said "that the rush of water being in an inclined direction towards the bottom, rather tends to scour it," but there is a failure to inform us whether the scouring leaves a true or a roughened surface. It is perfectly na- tural to suppose the latter is the case, and that the flap, not only a disadvantage but also an unnecessary append- age, did project the water downwards to form bridgeé holes, thereby retarding the vessel in shallow water and demanding greater power to do the work, a result similar to what it would be in the case of a vessel with a rough- ened bottom, as described in the paper of Capt. Suppan before the seventh congress. A screw, however, working in a tunnel with the air from the sides excluded and a free discharge aft seems to be a more desirable formation. It also seems that if the after portion of each side is made to form a rudder, as shown in Fig. 4, an additional advant- age is gained in being able to steer a straighter course, as the full surface of the rudders is brought into play, a re- sult not accomplished with the flap, as such a vessel is said to steer badly, the reason, no doubt, being that the water is projected downwards and away from the surface of rudder in proportion to the depression of the flap. With double or twin rudder its position in this arrangement not only affords protection, but also permits the quadrant or tiller being placed below the deck and also in a protected position. The conclusions drawn by me from the above in re the movement of a vessel through a fluid have been as fol- lows: 1. That all vessels create one or more waves. '2. That their chararcter at the stern is partly molded by the shape at this point. 3: That the height of waves above the normal water level is governed by the speed of vessel through the water and the latter's depth under the vessel. 4. That the wave at stern in shoal water answers the purpose of a flap, without restricting the flow aft and with least resistance. 5. That the discharge from a screw propeller should not only be free, but without restriction aft of it, no matter what the depth of water or at what speed the ves- sel moves through it. 6. That discharging the water downward at the stern will scour the bottom and form bridge holes to a greater extent than if discharged directly astern. 7. That the depth of bridge holes will be in proportion to the intensity of the discharge and proximity of the wheel to the bottom. 8. That a tunnel or form of stern directing the water to the screw propeller is valuable when its run limits the amount of skin friction and when it expands aft of the propeller. 9. That the propeller should be placed sufficiently far aft to limit the skin friction from the stream set in mo- tion. AUTOMATIC LIFE BOAT HANDLER. The Irvine-Lihon automatic life boat handler has re- ceived some fine indorsements during the past few months. It is intended to facilitate the launching of life boats. The contrivance, a sort of hand winch, is affixed to each davit, and occupies a deck space of 14 by 24 in., in addition to that occupied by the operator. The turning of a crank causes a bull pinion wheel to engage and turn a drive (cog) wheel, which operates a drum and hoists the boat out of the chocks. The detachment of the crank shaft disengages the bull pinion from the drive wheel, and con- nects the former with a clutch in a worm; this gears the worm with a cog wheel on a davit, and so turns the latter. When--with davit outboard--a safety pawl, the office of which is to keep the drum from turning, is released, the operator takes hold of a safety brake handler, which he eases up to quicken or holds down to check speed, and lets the boat go into the water. The same operations are required to bring the boat up and inboard. With this device the entire work of hoisting, swinging | out and lowering away is done by two men--one at each davit--in from one-half to one minute, and in any sort of weather. The men, as is shown, have perfect control, and thus can choose the auspicious moment in which to drop the boat as far away as possible from the ship's side --indeed. Captain Raymond says it "can be thrown out forty feet away from the ship." Wire rope is used for the falls, because it can neither burn, freeze nor expand to jam the block, as will manilla; and, as it runs on a drum, it is always clear and cannot kink. No guy is required, and the automatic handler can be attached to any davit in use today. It renders the life boat always ready--night and day--and without any prep- aration; there's only a handle to be turned. Its operation requires no expert or able seaman; the engineer crew is quite as much at home with it as is the deck department --indeed, landsmen can handle it with equally good results. It can be used on life rafts as well as on boats. Besides installing the device on the Providence, the new boat of the Fall River Line, the company has ordered it for the Priscilla and: Puritan. The Old Dominion Steamship Company has ordered a trial test. It is in use on the City of Erie, of the Cleveland and Buffalo Line; on the Indiana, of the Goodrich Line, of Chicago, and on the Summer. of the United States Army transport service and the General Meigs, of the quartermaster's depart- ment. There could be no better commendation of the device, as all will recognize who ate acquainted with the up-to-date manner in which this ably administered depart- ment equips and appoints this very important branch of the army service. The rights are controlled by James S. Barcus and W. F. -- Hallam, with offices at No. 111 Fifth avenue, New York, who have organized a company to market it. An electrically operated freight boat is running on the Volga river, between St. Petersburg and Rybinski, covering a distance of 600 miles or more. The boat, or rather barge, is of iron construction, and measures 74 meters long and ten wide. It has three screws. each of which is driven inde- pendently by a direct-current motor. Power is furnished by three Diesel engines of the four-cylinder type, direct coupled to continuous current generators, which furnish the current for the motors. The dynamos also furnish the cur- rent for lighting, pumps, and lifting apparatus of the boat.