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features which make it perhaps the most interesting of these modern de- signs. The steamship Turret, 280 ft. by 38: 4t. by~22 ft. 9 ins and '27> ft. 3 in. to turret deck (Fig. 21), built in 1893, and the first vessel of the type, presents the essential features which are now fammliar;* the turret is an integral part of 'the hull, and the turret deck stringer forms the top member of the girder, the turret base is rounded to permit free flow for bulk cargo, and the junction of the harbor deck with the side is rounded to avoid waste space or trimming charges. The principle of the trans- verse structure in the Turret, the out- standing feature of which is the open framework of strong stanchions and hold beams at comparatively wide in- tervals, remained unchanged until re- cently, the larger number of turret vessels built up to that time being, as shown on Fig. 22, vessels, 340 ft. by 45. tt. G6 intuby. 27 ite3 ano and 3A ft. 3 in. to the turret deck, having modified webs in, association with the built beams and _ stanchions. The largest development on these lines is to be found in (Fig. 23) three steam- ets for fhe B.° Co, 455 fe By 56 it.by 33: it, and? 41 ft: 91n. to, the turret deck. Longitudinally, these vessels are. pure single-deck ships in so far that all the material is con- tained on the outside walls, while the turret design of transverse framework is adhered. to, plus the .addition of large webs between the hold beams. These: vessels each carry -over 2,000 tons of water in a deep midship tank 36 ft. long, of which the turret deck is the crown, and the base of which is subject to a pressure of consider- ably over a ton per square foot, while the central wash division stops at the level of the broadside stringer. About two years ago a novel principle in construction was 'introduced by Messrs. Doxford, as shown in Fig. 24, where the ship is kept in shape by wide web frames at the hatchway ends arranged continuously round the skin of the ship, of such form and strength and having such strong at- tachments to the double bottom (which is increased in depth) that the complete framework should be inca- 'pable of deflection in any direction, and permits of stanchions and beams below the turret deck being entirely omitted. At the present time Messrs. Doxford are building to the design shown in Fig. 25, where, by fitting large tube stanchions at the hatchway ends under the stiff turret sides, in association with diagonal ties in _ pairs, an interesting combination of material has been evolved. and with this, "TAE. MARINE. REVIEW Fig. - 26° (Plate III.). shows' « the Priestman' self-trimmer Universe, «in which the top sides are sloped from the upper or turret deck level to :a narrow platform at the harbor. deck, and the internal structure is of the wide-spaced open franaework type. It is of interest gto note the double-bot- tom constructiéns and absence of in- tercostals to the bottom shell. Messrs. Sir Raylton Dixon have built a number of vessels which are known as "Harroway & Dixon's Pat- ent,' which there are sloping ballast tanks in the corners of the top sides as' shown in Fig. 27, and where the stiffness and strength of top sides ob- tained by this form of construction, permit of very. wide hatchways. As the vessels are so designed that it is practically impossible to conceive of deflection in the corner tanks between the bulkheads, the hatchways can be made practically the whole length of each hold, and the builders are en- abled to dispense with stanchions and beams in the holds. The largest ves- sel: yet built on this plan is 390 'ft. by S570 an. by 26 ft--6 ing aad 35 ft. (see. Fig. 28), where a shelter deck is fitted above the upper deck, as with the original single-deck design, 'practically unlim- ited expansion in dimensions of ships should be possible. Fig. 29 shows a steamer 305 ft. by 46 ft. 9 in. by 24 ft, being. built by the Sunderland Shipbuilding Co., to the design of Mr. Henry Burrell, which embodies several interesting features; the double bottom is sloped up the sides of the vessel so as to form a self-trimming trough for coal or grain, and the upper works are ar- ranged so as to give free flow for bulk cargo; while the sides, trunk way, and decks are so supported by what, for want of a better name, may be called cantilever webs, and by comparatively closely spaced bulk- heads, that stanchions are wumneces- sary. The construction -is simplified in this case by adopting a spacing of 32:41n. fer the frames. Fig. 30 shows the "Ropar? trunk, in which the ship is of ordinary deep frame -construction up to the harbor deck, which is kept apart by strong beams at hatchway ends, etc., while the trunk. is supported by webs, cross plating, and strong built center stanchions in -association therewith. In the earlier vessels of the type, built stanchions were fitted under the trunk sides at comparatively close in- tervals, and the trunk was a com- paratively light erection, experience has shown the former to be unneces- sary, and the desirability of re-ar- 39 ranging the material'so 'as to make the trunk the effective top: membér of the girder. - Av remarkable +devel- opment of this design is shown" in Fig. 31, where the trunk sides are doubled, and spaces thus formed carry water ballast; the upper struc- ture is supported by large webs, the engines are placed. aft, there are two hatchways, each over 100 ft. in length, and the hold is in, one length from collision bulkhead to machinery space. It must be admitted that the design is abnormal, and may be taken as to some extent experimental; but its conception is indicative of the freedom which has come over the spirit of shipbuilders during recent years. If attacked solely from the point of view of economy and efficiency of design and as a problem in engineer- ing, unhampered by preconceived ideas of construction and trade re- quirements, it seems to be obvious that the natural design of a_ ship- shaped girder would be one which would have the material disposed en- tirely on the circumscribing walls, but misconceptions of true principles in» design are unavoidable legacies from 'previous constructive methods. The influences which' have caused per- sistence in bad disposition of longi- 'tudinal material are not easily under- stood, perhaps they follow from the influence of wood 'shipbuilding meth- ods, while the retention of the name "Main," as applied -to a deck: which was not the top deck, may have had the effect due to 'suggestion: We have certainly grown up amid the conception that numerous tiers of beams .are . natural .and 'that. 'their omission demands compensation, in- stead of what seems to be the sound idea exemplified by Messrs. Brunel and Scott Russell half a century ago, that the ideal structure would have the longitudinal material massed <on the upper deck, bottom, and_ sides; the transverse members would be of the simplest form and fewest number possible, with their contributory ele- ments as far apart as the thickness of plating would permit; while addition- al tiers of beams or layers of plating would be regarded as unscientific and to be fitted only under compulsion of trade conditions, but that, when fitted, the best use-had to be made of them as factors in, the structural equation, in order to minimize what must nec- essarily be wasteful in weight, just as is the central core of.a shaft or any other Massing -- of. material 'in the wrong place. It appears to me that a: study of the diagrams will. show that the tend-