Page:EB1911 - Volume 19.djvu/974

OANNES, in Babylonian mythology, the name given by Berossus to a mythical being who taught mankind wisdom. He is identical with the god Ea (q.v.), although there may not be any direct connexion between the two names. Berossus describes Oannes as having the body of a fish but underneath the figure of a man. He is described as dwelling in the Persian Gulf, and rising out of the waters in the daytime and furnishing mankind instruction in writing, the arts and the various sciences. The culture-myth on which the account of Berossus rests has not yet been found in Babylonian literature, but there are numerous indications in hymns and incantations that confirm the identification with Ea, and also prove the substantial correctness of the conceptions regarding Oannes-Ea as given by Berossus.  (M. Ja.) 

OAR (A.S. ár; M. Eng. ore; Lat. rēmus; Gr. ἐρετμός: Sans. aritra; Fr. rame; Ital. Span., Port. rama), the instrument used for propelling a boat in rowing (q.v.). The word “oar” is probably derived from an old 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 action of the power employed by means of the oar against' a thowl, or rowlock, from that of the more primitive paddle, where the power is gained by the action of one 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 order, in which the weight lies between the power and the fulcrum The point at which the power pressed the arm of the lever against the weight in rowing would soon attract attention by the frequent breakage of the paddle so employed. Experience would demand a thicker loom, and would soon teach the desirability of increasing the leverage where possible, and upon this would arise naturally the 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 (τροπός, τροπωτήρ), familiar to ancient Greek and modern Levantine, and, in northern and western waters, the invention of the “button,” with which in various shapes the rowing world is now provided. Other devices, such as a hole bored in a piece of wood attached to the oar, or even a metal ring, will, in different localities, be found answering the same purpose.

In the early stages of the transition from paddling to rowing, the oar would naturally be used at an acute angle vertically to the boat’s side. In paddling the upper hand is used to push from you, the lower hand to pull towards you. But in rowing both hands are used to pull towards you. As 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 wrist turned inward towards the 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 character of the stroke, but also the requirements as to the length of the oar and the breadth of the blade. The form of the oars given in the representations of early Egyptian ships is suggestive of paddles used as oars. Paddle-shaped also are the oars of the Phoenician ships shown on the Assyrian sculptures at Koyunjik (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 Roman galleys are generally heavy and clumsy enough in appearance. Still they are veritable oars, not paddles. The material of which the ancient oars were usually made was pine, which then, as now, was most suitable for the purpose, being tough and comparatively light and easily shaped as regards loom and blade.

The oars of the Attic trireme were, if we may judge by those of which only we have the measurement recorded, not much longer for the upper bank than those of a modern racing eight, while those of the middle and lower banks could not have been much longer than those used now in the whalers and dinghies of the Royal Navy. As the oarsmen on either side probably sat in the same vertical 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 vessel’s sides (cf. Aristotle, Mechanica, v.) No doubt in vessels of larger size the upper tiers of oars would be longer, and, if we are to believe Callixenus, as cited by Athenaeus, in the great ship of 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 period and those of the Byzantine and medieval galleys. In the medieval galley by the invention of the “apostis,” a framework on which the thowls were fixed, sufficient room was given for the play of longer oars, and, as the necessity of combining speed with greater carrying power in the galley became pressing, the arrangement alla scaloccio came into 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 beech being used as well as pine.

Table showing Oars used in Royal Navy.

Description of Vessel.	Oars.		Blades.		Material.	No. allowed.
	Length.	Thickness.	Length.	Breadth.
1. Launches, 42′	17–16	17 21/4 –17/8	5′ 8″	51/2″	White ash or Fir	18
	. .	16 21/8 –13/4	5′ 4″	53/8″		. .
2. Pinnaces, 36′	17–16					16
32′	16–15	15 21/8 –13/4	5′ 0″	51/4″		14
30′	16–15	. .		. .		12
3. Cutters,34′	15–14	14 2–15/8	4′ 8″	51/8″		14
32′	15–14	. .	. .	. .		14
30′	15–14	. .	. .	. .		12
28′	15–14	. .	. .	. .		12
26′	15–14	. .	. .	.		10
,,gig, 20′	15–14	. .	. .	. .		4
4. Galleys 32′	17–16	. .. .	. ..	. .		6
5. Gigs, 30′	17–16	. .	. .	. .		6
28′	17–16		. .	. .		6
6. Whalers,27′	15–14					5
	. .	13 2 –15/8	4′ 4″	5″		. .
7. Skiff dinghies, 16′	10–8	10 15/8 –13/8	3′ 4″	43/4″		4*
	. .	9 15/8 –13/8	3′	45/8″		. .
8. Dinghies,131/2′	10–8	8 15/8 –13/8	2′ 10″	41/2″		4

 *Allowed spoon-blade oars.

Notes.—(1) Since 1893 some curved or spoon-bladed oars have been made at Devonport. (2) There is no record of buttons being used, but on fir oars, which were covered with canvas on the loom, it was sometimes customary to work a Turk’s head at the end of the canvas for ornament. (3) As regards sweeps, they used to be made of ash and were 30 ft. long. They were used last in training brigs, but there is no record of them for the last twenty years.

In the Mediterranean the galley propelled by oars long remained the principal type of war vessel. In the Atlantic, and in the northern seas, it was otherwise.

The employment of artillery on board ship gradually determined a change in the method of propulsion. The use of sails