SKILLS IN NAVAL TACTICS |
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The science of hydrodynamics developed, in addition to hydrostatics |
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George ATWOOD, The Construction and Analysis of Geometrical Propositions, Determining the Positions Assumed by Homogeneal Bodies Which Float Freely, and at Rest, on a Fluid's Surface; Also Determining the Stability of Ships, and of Other Floating Bodies, .' Philosophical Transactions of the Royal Society of London , Vol.86, 1796, p.120 the ship being continually impelled by the force of stability, revolves round an horizontal axis, passing through the centre of gravity with an increasing velocity, till it arrives at upright position ; and afterwards with a velocity constantly retarded, till it arrives at the greatest inclination on the other side. The rolling of the ship, with alternate acceleration and retardation of the angular velocity, will evidently depend on the force by which the angular motion is generated; that is, on the force of stability, and its variation corresponding to the several distances of the vessel from its upright position. |
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Tacticians focused on the mobile elements: the wind |
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The shape of the ships was studied to give better mobility | Abraham REES, Naval Architecture 1819-20 , in The Cyclopaedia; or Universal Dictionary of the Arts, Sciences and Literature , Newton Abbot: David and Charles,1970, p.3 Those who would diminish the breadth have alleged, and truly, that a narrow vessel meets with less resistance in passing through the water, and by increasing in length, the vessel will drive less to leeward, and the waterlines consequently be more delicately formed to divide the fluid: on the contrary, a ship's being broader at the line of flotation will admit of being narrower on the floor, particularly at the fore and after parts; that by being broader it can carry more sail, and more readily rise upon the waves than a narrow one . In order that the ship should steer well, and quickly answer her helm the water-lines, as they approach the stern-post, may tape handsomely into the same, so that every succeeding waterline, as they approach nearer the keel, may have their curvature more delicate |
(these extracts are taken from my article in Art et Nation en Grande-Bretagne au XVIIIe siècle, Paris: PSN, 2006) |