1. Hydrodynamics. (See quot. 1906.)
1873. J. C. Maxwell, Electr. & Magn., § 648 II. 260. If φ is constant for any curve, there is no current across it. Such a curve is called a Current-line or a Stream-line.
1882. Minchin, Unipl. Kinemat., 151. When the motion becomes steady, each line of flow becomes the actual path of a fluid particle, which is called a stream-line.
1906. Hor. Lamb, Hydrodynamics (ed. 3), 17. A ‘line of motion’ or ‘stream-line’ is defined to be a line drawn from point to point, so that its direction is everywhere that of the motion of the fluid. Footnote, Some writers prefer to restrict the use of the term ‘stream-line’ to the case of steady motion.
b. attrib., as stream-line motion; stream-line form, that shape (otherwise called ‘fish body’ form) of a solid body that is calculated to meet with the smallest amount of resistance in passing through the atmosphere.
1898. Hele-Shaw, in Rep. Brit. Assoc., 136. Stream-line Motion of a Viscous Film.
1909. C. C. Turner, Aerial Navig. To-day, viii. (1910), 131. Bodies having ‘streamline’ form present the least resistance to the air. Pure streamline form is, roughly speaking, pear-shaped, the blunt end foremost.
2. (See quot.)
1885. Tait, Prop. Matter, iv. § 83. 70. The line of steepest slope at any point of a surface is represented on the map by the shortest line which can be drawn to the nearest contour line. Thus it cuts the contour lines at right angles, and is the path along which a drop of water would trickle down. It is therefore called a Stream-line.
