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See also:OAR (A.S. kr; M. Eng. ore; See also:Lat. remus; Gr. iperw5s : Sans. aritra; Fr. rame; Ital. Span., See also:Port. Yana) , the See also:instrument used for propelling a See also:boat in See also:rowing (q.v.) . The word " See also:oar " is probably derived from an old See also:root ar, meaning to drive, to force away (cf. ar-ar-e, aratrum, plough) . Such an appellation would easily be suggested by the visible difference in the See also:action of the See also:power employed by means of the oar against a thowl, or See also:rowlock, from that of the more See also:primitive See also:paddle, where the power is gained by the action of one See also:hand against the other . In the development of rowing from paddling the task of shaping the instrument of propulsion must have followed gradually the necessities indicated by use . In rowing, as well as in paddling, the leverage is of the second See also:order, in which the See also:weight lies between the power and the fulcrum . The point at which the power pressed the See also:arm of the See also:lever against the weight in rowing would soon attract See also:attention by the frequent breakage of the paddle so employed . Experience would demand a thicker See also:loom, and would soon See also:teach the desirability of increasing the leverage where possible, and upon this would arise naturally the See also:practical questions of the length of the oar, of the breadth of the blade, and of the right proportion of the parts of the oar, inboard and outboard, to each other . Then would also occur the problem of how to keep this proportion, which in practice would be liable to disarrangement by the slipping outward of the oar during the recovery from each stroke . Hence would arise the use of the thong (rpoabs, rpoircari7p), See also:familiar to See also:ancient See also:Greek and See also:modern Levantine, and, in See also:northern and western See also:waters, the invention of the " See also:button," with which in various shapes the rowing See also:world is now provided . Other devices, such as a hole bored in a piece of See also:wood attached to the oar, or even a See also:metal See also:ring, will, in different localities, be found answering the same purpose . In the See also:early stages of the transition from paddling to rowing, the oar would naturally be used at an acute See also:angle vertically to the boat's See also:side . In paddling the upper hand is used to push from you, the See also:lower hand to pull towards you . But in rowing both hands are used to pull towards you . As See also:long as the oar was used at an acute angle vertically to the boat's side, the position of the upper hand on the oar would have to be reversed, as it would more easily grasp the oar with the See also:wrist turned inward towards the See also:body . In many of the earlier representations of rowing this position of the upper hand seems to be indicated . This distinction should not be lost sight of, as the position of the hands on the oar affects not only the See also:character of the stroke, but also the requirements as to the length of the oar and the breadth of the blade . The See also:form of the oars given in the representations of early See also:Egyptian See also:ships is suggestive of paddles used as oars . Paddle-shaped also are the oars of the Phoenician ships shown on the See also:Assyrian sculptures at Koyunjik (See also:Layard), the date of which is about 700 B.C . The same form is seen on some of the early vases, but in some that are attributed to two centuries later the form is modified, and the oar blade proper begins to take shape . The types exhibited in the representations of the See also:Roman galleys are generally heavy and clumsy enough in See also:appearance . Still they are veritable oars, not paddles . The material of which the ancient oars were usually made was See also:pine, which then, as now, was most suitable for the purpose, being tough and comparatively See also:light and easily shaped as regards loom and blade . The oars of the See also:Attic trireme were, if we may See also:judge by those of which only we have the measurement recorded, not much longer for the upper See also:bank than those of a modern racing eight, while those of the See also:middle and lower See also:banks could not have been much longer than those used now in the whalers and dinghies of the Royal See also:Navy . As the oarsmen on either side probably sat in the same See also:vertical See also:plane, the inboard portion of the oars amidships was longer than the inboard of those fore and aft, having to conform to the curvature of the See also:vessel's sides (cf . See also:Aristotle, Mechanica, v.) . No doubt in vessels of larger See also:size the upper tiers of oars would be longer, and, if we are to believe Callixenus, as cited by See also:Athenaeus, in the See also:great See also:ship of See also:Ptolemy the oars of the upper tier were over 50 ft. in length with handles leaded so as to equalize the weight inboard and outboard . It is difficult to trace any detail of difference between the oars of the Roman See also:period and those of the See also:Byzantine and See also:medieval galleys . In the medieval See also:galley by the invention of the " apostis," a framework on which the thowls were fixed, sufficient See also:room was given for the See also:play of longer oars, and, as the See also:necessity of combining See also:speed with greater carrying power in the galley became pressing, the arrangement See also:cilia scaloccio came into See also:vogue, employing four or five or even seven men to each of the long sweeps by which the galleys and galleasses were propelled . For these large oars we hear of ash and See also:beech being used as well as pine . In the Mediterranean the galley propelled by oars long remained the See also:principal type of See also:war vessel . In the See also:Atlantic, and in the northern seas, it was otherwise . The employment of See also:artillery on See also:board ship gradually deter- See also:mined a See also:change in the method of propulsion . The use of sails 19 Table showing Oars used in Royal Navy . Description of Oars . See also:Blades . Material . No . Vessel . Length . Thickness . Length . Breadth . allowed . I . . 17—16 17 2y—I e 5' 8" 51" 18 Launches, 42' 162s I* 5'4" 51" 2 . Pinnaces, 36' . 17-16 .. 16 32' . 16—15 15 2*—Is 5' 0" 54" 14 30' . 16—15 .. 12 3 . Cutters, 34' . 15-14 14 2 —Is 4' 8" 5a" 14 32' . 15-14 .. . . . . (r, 14 30' . 15—14 .. . . .. w 12 28' . 15—14 .. . . . . C I0 26' 15—14 .. . . .. w lo See also:gig, 20' . 15—14 .. . . . . , 4 4 . Galleys 32' . 17-16 .. . . . . 6 5 . Gigs, 30' 17-16 3 6 28' . 17-16 .. . . 6 6 . Whalers, 27' . 15-14 • • • • 5 i " v 7 . Skiff dinghies, 16' . io-8 1 2 _-1IIe 4" 44" 4* Io I 9 a ' 4s" 3' 8 . Dinghies, 13z' . Io-8 111-11 2' 10" 41" 4 8 * Allowed See also:spoon-blade oars, Notes.-(1) Since 1893 some curved or spoon-bladed oars have been made at See also:Devonport . (2) There is no See also:record of buttons being used, but on See also:fir oars, which were covered with See also:canvas on the loom, it was sometimes customary to See also:work a Turk's See also:head at the end of the canvas for See also:ornament . (3) As regards sweeps, they used to be made of ash and were 3o ft. long . They were used last in training brigs, but there is no record of them for the last twenty years . became necessary, and remained dominant until the introduction of See also:steam (see SHIP) . But as See also:late as the See also:time of the See also:Spanish See also:Armada, and even later, large See also:sea-going vessels were provided with long sweeps which came into use when sailing was not available . In our own time, in the lighters on tidal See also:rivers, may be seen long oars, plied by one or two or more men, which recall the type of oars once in See also:general use in large galleys three centuries ago . The oars used by the Northmen were, to judge by the remains discovered along with old See also:Viking ships 1 at Gokstad and else-where, very similar to those in use at the See also:present time in the fishing boats around our coasts . Those of the large See also:craft were, to judge by the length of one found whole, somewhat over 18 ft. in length with a 5-in. blade and a See also:diameter of 3 in. halfway down the loom . Some smaller oars, evidently used for boats, measured 1r ft. with a 4-in. blade . The oars were of pine, and the looms of some of them showed a groove cut for a clamp at the See also:place where the oar rested on the See also:sill of the rowlock . Comparing these oars with the measurements given below of oars now in use in the Royal Navy, it is apparent that there is no great difference in type between them . Passing on to oars used on rivers and fresh See also:water generally, we find the type differs considerably from that of the oars used in sea-going craft . The See also:chief difference consists in the shape of the blade, which, instead of continuing the straight See also:line of the loom in its expansion to its proper breadth, is fashioned in a See also:curve calculated to offer a rigid resistance to the water during the stroke ? The loom below the button is not rounded but is more of an See also:oval to the front with a See also:flat back . From the oval front a spine runs down into the blade, in some cases to nearly See also:half its length . During the last few years the so-called " girder " oars, with much thicker looms but See also:double grooved along their length, have been used for racing purposes . This invention gives additional strength and stiffness, without increasing the weight of the oar, which varies a little but is usually about 8 lb . The blades vary much in breadth, as indeed do the oars in See also:total length, and in proportion of inboard to outboard . The necessities of the Aiding seat in racing boats have given rise to much difference of See also:opinion among rowing men as to the right proportion . In the middle of the 19th See also:century the use of square looms inboard, and of a button to turn inside and against the thowl, was See also:common, and most oars had a small slab of hard wood let in below the button, so as to See also:save the oar from See also:wear and See also:tear at the rowlock . But since See also:round looms came into vogue the round See also:leather See also:ear has taken the place of the old square button, and the loom is covered with leather for some inches above and below this so as to protect it from See also:abrasion . Of late the introduction of swivel rowlocks for racing boats has caused a further modification in the form of buttons . Swivel rowlocks have come into general use for sculling boats, pair oars and coxswainless fours . But as yet they do not appear to have captured the racing eight, except in a few instances . Neither crews nor coaches in See also:English waters seem inclined to See also:part with the time-honoured rhythmic See also:music of the oar in the rowlock, which from the days of antiquity even until now has, to practised ears, told its own See also:tale as to the See also:crew being together or not in the stroke . In the See also:case of racing eights, when the round loom oars superseded the square loom, the early patterns were commonly (e.g. in 1857) 12' 6" over all, 3' 8" inboard, with a long blade 41" to 5" in breadth . These were succeeded by a See also:pattern 12' 6" over all, 3' 6" inboard, with a much shorter blade 6" broad . Since sliding seats came in the See also:average oar has been 12' 4" over all, 3' 81" inboard, with 52" to 6i-," blades . The modern racing oar may be said to date from 1869, the See also:year of the See also:Oxford and Harvard See also:race at Putney . Until very lately no material alteration had taken place in this pattern, except in the See also:matter of width of blade . Some authorities, however, are, as has been 1 See Viking Ship, Nicolaysen (See also:Christiania, 1882) . 2 Since 1890 the curved blade seems to have been adopted in some cases in the oars made at Devonport for the Royal Navy.said above, far from satisfied with the present average oar, and are using shorter patterns, ii' 1o" or 12' o" over all, 3' 7" inboard, and 7" blades . Single grooved oars were first made in See also:America . But with the single groove a side weakness is often See also:developed in the loom, and hence the double girder, invented by G . Ayling, has generally superseded the single groove, though many oarsmen prefer the See also:box loom by the same inventor . It is clear, however, that no finality has been reached in the making of oars . Tubular oars, first introduced at See also:Henley by the Belgian crew in 1906, are now being tried, with circular or quadrangular bores, strengthened by the insertion of an See also:aluminium See also:shell . For much of the See also:information above given respecting the See also:recent developments in oar-making for racing purposes and See also:river work, the writer is indebted to Messrs Ayling & Sons of Putney, whose patented inventions and improvements are well known to rowing men . (E . |
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