What is "wave-line theory"

Wave \Wave\, n. [From Wave, v.; not the same word as OE. wawe, waghe, a wave, which is akin to E. wag to move. [root]138. See Wave, v. i.]

1. An advancing ridge or swell on the surface of a liquid, as of the sea, resulting from the oscillatory motion of the particles composing it when disturbed by any force their position of rest; an undulation.

   The wave behind impels the wave before.
   --Pope.

2. (Physics) A vibration propagated from particle to particle through a body or elastic medium, as in the transmission of sound; an assemblage of vibrating molecules in all phases of a vibration, with no phase repeated; a wave of vibration; an undulation. See Undulation.

3. Water; a body of water. [Poetic] ``Deep drank Lord Marmion of the wave.''
   --Sir W. Scott.

   Build a ship to save thee from the flood, I 'll furnish thee with fresh wave, bread, and wine.
   --Chapman.

4. Unevenness; inequality of surface.
   --Sir I. Newton.

5. A waving or undulating motion; a signal made with the hand, a flag, etc.

6. The undulating line or streak of luster on cloth watered, or calendered, or on damask steel.

7. Something resembling or likened to a water wave, as in rising unusually high, in being of unusual extent, or in progressive motion; a swelling or excitement, as of feeling or energy; a tide; flood; period of intensity, usual activity, or the like; as, a wave of enthusiasm; waves of applause. Wave front (Physics), the surface of initial displacement of the particles in a medium, as a wave of vibration advances. Wave length (Physics), the space, reckoned in the direction of propagation, occupied by a complete wave or undulation, as of light, sound, etc.; the distance from a point or phase in a wave to the nearest point at which the same phase occurs. Wave line (Shipbuilding), a line of a vessel's hull, shaped in accordance with the wave-line system. Wave-line system, Wave-line theory (Shipbuilding), a system or theory of designing the lines of a vessel, which takes into consideration the length and shape of a wave which travels at a certain speed. Wave loaf, a loaf for a wave offering. --Lev. viii. 27. Wave moth (Zo["o]l.), any one of numerous species of small geometrid moths belonging to Acidalia and allied genera; -- so called from the wavelike color markings on the wings. Wave offering, an offering made in the Jewish services by waving the object, as a loaf of bread, toward the four cardinal points. --Num. xviii. 11. Wave of vibration (Physics), a wave which consists in, or is occasioned by, the production and transmission of a vibratory state from particle to particle through a body. Wave surface.

   1. (Physics) A surface of simultaneous and equal displacement of the particles composing a wave of vibration.

   2. (Geom.) A mathematical surface of the fourth order which, upon certain hypotheses, is the locus of a wave surface of light in the interior of crystals. It is used in explaining the phenomena of double refraction. See under Refraction.

      Wave theory. (Physics) See Undulatory theory, under Undulatory.