long piece of timber, flat at one end and round or square at the other; and which being applied to the side of a floating vessel, serves to make it advance upon the water.

That part of the oar which is out of the vessel, and which enters into the water, is called the blade or wash-plate; and that which is within board is termed the loom, whose extremity being small enough to be grasped by the rowers, or persons managing the oars, is called the handle.

To push the boat or vessel forwards by means of this instrument, the rowers turn their backs forward, and, dipping the blade of the oar in the water, pull the handle forward so that the blade at the same time may move aft in the water: but since the blade cannot be so moved, without striking the water, this impulsion is the same as if the water were to strike the blade from the stern towards the head: the vessel is therefore necessarily moved according to this direction. Hence it follows, that she will advance with the greater rapidity, by as much as the oar strikes the water more forcibly. Thus it is evident, that an oar acts upon the side of a boat. boat or vessel like a lever of the second class, whose fulcrum is the station upon which the ear rests on the boat's gunnel. In large vessels, this station is usually called the row-port; but in lighters and boats it is always termed the row-lock.