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32 ae MARINE REVIEW AND MARINE RECORD. boiler used for surface work and partly in special tanks. An in- board profile of the last Nordenfeldt No. 4, built in England, sold to the Russian government, and lost on the coast of Den- mark while making the passage under her own power, is also shown in one of the illustrations. This vessel had a leneth of 125 ft. a light displacement of 160 tons, and a submerged dis- placement of 245 tons. With 150 lbs. of steam her engines indi- cated 1,000 H. P. Her estimated speed was 15 knots on the sur- face in the licht condition and 5 knots submerged. In the latter condition the radius of action was expected to be 20 knots. Coal was employed as fuel, and the bunker capacitv was sufficient for a radius of action in the light condition of about 1,000 miles at a speed of 8 knots. By employing some of the ballast tanks as bunkers this radius could be more than doubled. She was de- signed to do her submerged work with about 500 lbs. of reserve buoyancy, which was carried under by two steam-driven down- haul screws, one at the bow and one at the stern. The valves of the down-haul engines could be controlled by hand or automati- cally through a connection with a hvdrostatic piston. 'These screws were relied upon to maintain depth and control in the vertical plane. 'the only remaining element of novelty was the employment for the first time of the automobile torpedoes, which, in the first Nordenfeldt, were carried in exterior tubes, and in the one illustrated, in the internal tubes. 'The trials of this No. 4 in the light condition were satisfactory, but as a submarine boat she was almost a total failure, as the down-haul screws provec inadequate to prevent yawing, so that when under water she, like the Plongeur, took .uarge and alternatelv sought the surface and the bottom, duplicating in this respect the behavior of the three previous vessels. PRINCIPAL DEFECT OF NORDENFELD1?'S DESIGN. The principal seat of difficulty in all the Nordenfeldt boats was undoubtedly the large free liquid surface in the various tanks, resulting in a shifting center of gravity and a serious de- crease of the designed stability. Large tank capacities were a necessary feature of Nordenfeldt's design, but the bad features thereof could have been largely reduced by subdivision. In No. 4 at least the inherent defects of the design in this respect were aggravated by mistakes in calculation, resulting in natural trim by the stern. This was corrected by an amount of fixed ballast forward, so great that certain of the ballast tanks could not be entirely filled without overrunning the permissible weights. These vessels were designed to maintain the horizontality of their longi- tudinal axis at all times--sinking, rising and running submerger --and most signally failed to meet expectations in that respect, as had previously boats of similar form designed on the same principle. Notwithstanding this, and neglecting the partial suc- cesses of predecessors working along different lines, Nordenfeldt continued to maintain the absolute necessity of this property. His dogma in this respect was widely accepted and so tenaciously held that some of its supporters continued until a very recent date to prove theoretically to their own satisfaction the utter impossi- bility of accomplished and widely known facts. The last type selected for illustration was designed by M. Goubet in 1885, and began her trials in 1889. An inboard profile of the vessel with explanatory legend is among the illustrations. None of the main features of the design, namely, equality of buoyancy and weight, control in the vertical plane by the auto- matic longitudinal shift of water ballast and a steering propeller, were really novel, but it merits attention as the most successful example of its class. The small experimental boat proved suc- cessful on trial, thanks to the care taken with details; note, for instance, the minute subdivision of the ballast tanks. 'That the type has not been perpetuated is doubtless due to the absence of reserve buoyancy and the unsuitability of the control system for the forms and dimensions required to-meet practical conditions. . The three leading nations in the construction of the modern submarine are France with a total of forty-four built, building or provided for; Great Britain with ten, and the United States with seven. The subject has been taken up by the other nations, but as their work is still in the experimental stage, and but little reli- able data is available as to progress, it need not be considered here. Great Britain is working along American lines, and there- fore the present review may. be confined to the French and Amer- ican boats. The French fleet of modern submarines dates from 1886, when the then minister of marine, Admiral Anbe, ordered the construction cf an experimental boat the Gymnote--length, 59 ft. ; diameter, about 6 ft.; displacement, 30 tons--from the joint de- sign of Dupuy de Lome and Gustave Zede. Her spindle-shaped hull was constructed of steel throughout, tank service was ob- tained from electrically driven pumps, and also from a compressed air system, which, in additicn, furnished air for breathing pur- poses. A telescopic conning tower was provided for observation on the surface, and an optical tube for use below. The power installation consisted of a storage battery and a 55-H. P. motor driving a single screw. The reserve buoyancy was driven under from the propeller by inclining the axis of the boat, a pair of hor- izontal stern rudders being provided for that purpose. The trials beginning in 1888 were very exhaustive, and led to the re- moyal of the telescopic tower and a number of other alterations, : pncipally in the propelling and diving gear. Eventually satis- eed results were obtained at a submerged speed said to be ) knots. ee (Nov. >. The Gymnote was followed by the Gustave Zede, ordered in 1890 from the designs of M. Romazzotti, and launched in 18or. The design followed closely that of the original Gymnote, but on a much larger scale, the dimensions being: Length, 159 ft.; diameter, 12 ft. 4 in.; submerged displacement, 266 tons. The hull was of bronze throughout. She was fitted with a single screw, driven by two 360-H. P. motors, fed by a storage battery of 720 Laurent Cely cells. She carried three Whitehead tor- pedoes and cne bow tube. The step from the Gymnote to the Zede proved too large a one and extensive trials and many alter- ations were necessary befcre the Zede gave satisfaction. Evi- dently the designer of the Zede did not take full advantage of the data derived from the Gymnote, as the alterations in the two cases were along the same lines. The telescoping conning tower was abandoned for a fixed one, the set of horizontal rudders at the stern was supplemented by the addition of a set amidships and a set forward, and the voltage and power were cut in two by the removal of half the cells from the battery. Reports as to her speed in ner final form are conflicting, but it is probably about 8 knots. Her behavior in other respects is evidently good as is shown by her own performances in various maneuvers, note- Fig. 6. Goubet. A, conning tower: BB, compressed air tanks; CC. storage batteries; DD, ballast tanks; E motor; F, adjustable screw; GG, pumps; H, wheel for adjust- ing screw; I, trimming tank; J, detachable weight. worthy the torpedoing of the Martel in the harbor of Ajaccio during the maneuvers of 1901. Even while the Zede was build- ing, it was apparently realized that her dimensions were extreme for the type, and an intermediate vessel, the Morse, was ordered from the plans of M. Romazzotti. Her particulars are as fol- lows: Length, 118 ft.; diameter, about 8 ft. 6 in.; displacement, 146 tons; horse power, 350; armament, one bow tube and two side carriers of the Drzewiecki type. The design follows very closely that of the improved Zede.. Her construction was long delayed on account of proposed improvements, and she was not launched until 1899. On trial she developed a speed of 12.3 knots on the surface and about 8 submerged--excellent results for Her type. While the Zede and Morse were in hand, a different type known as the submersible and represented by the Narval was under de- velopment. 'This type is fitted with a separate power installation for propulsion cn the surface and for recharging batteries, thus rendering the boat independent of a base so far as power is con- cerned, greatly increasing the radius of action and diminishing the © risk of total disability. THE MODERN FRENCH SUBMARINE. In 1896 the minister of marine invited designs for a sub- marine not exceeding 200 tons displacement, which should carry two torpedoes ready for launchine and have a radius of action on the surface of 100 miles at 12 knots; submerged of 10 miles at 8 knots. Of the twenty-eight designs submitted in accordance with this call, three were awarded prizes, though the first prize of 10,000 francs was withheld. From among these designs that of M. Laubeuf was later selected for development and finally took substance in the Narval, launched in 1899. Her particulars are: Length, 111 ft. 6 in.; beam, 12 ft. 4 in.; displacement, light, 106 tons; submerged, 200 tons. A water-tube boiler burning petro- leum supplies steam ior a 250-H. P. triple-expansion engine used for surface propulsion and for charging air flasks and recharging the storage battery. As to the details of the electric installa- tion, little is known except that two motors are employed. The armament consists of four torpedoes in Drzewiecki carriers. The speeds and radii of action are reported to be as follows: Maxi- mum surface speed, 12 knots: radius at that speed, 242 miles; radius at 8 knots, 625 miles; maximum submerged speed, 8 knots; radius at that speed, 25 miles; radius at 5 knots, 70 miles. As to submarine qualities, the design of the Narval follows the Morse, and aside from the double power installation the only item of particular interest is the construction adopted for the hull, which is a development of the system employed in the first Holland boat, namely, complete double bottoms or rather double skins, the en- closed space being entirely full of water when submerged. 'The French authorities appear to be well satisfied with the Narval, except as to the tengtn of time necessary to pass from the light to the diving condition, which is excessive. In later boats of her class that time has been reduced somewhat-- but the fault has not been wholly eradicated. The exact composition of the total authorized fleet of forty- four cannot now be told, as the details of a number of the boats authorized have not yet been settled, and the experience with the