Line.
1. (Fiber.) The tiner and longer stapled flax separated from the shorter, tow, by means of the hackle (which see).
2. (Printing.) An arrangement of letters and words across a page or column. 3. The twelfth of an inch. 4. A measuring cord, or one for tying or suspending objects, as a tape-line, clothes-line, chalk-line, etc.
5. (Machinery.) a. The truth of position; as an engine in line, that is, the motions of the piston, pitman, and crank-wrist in the same plane, and at right angles to the axis of the fly-wheel. b. The line of centers. The dead point of a crank, when the connecting-rod and crank are in a straight line.
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6. (Fortification.) A rampart. Continued lines are used to inclose a front or to connect principal works with one another by a continuous parapet. Redans, tenailles, or bastions are placed at intervals, for flank defense, and give rise to the terms, — Redan line (m). Tenaille line (n). Bastion line (o). Indented lines (p) have a succession of faces and flanks at right angles. The faces are four times the length of the flanks; the latter have an enfilading fire on the faces of the parapet. Names defining position and relation are: — Line of defense: extending from the projecting angle of a work to the exterior extremities of the flanks which defend it. Line of circumvallation: a belt of field-works two or three miles from the place invested, facing the country. Line of contravallation: a belt of field-works facing the place attacked. Line with intervals: one having detached works which command the intervening space and enable them to support each other.
7. (Shipbuilding.) A delineation of the form of a vessel, representing vertical and horizontal sections. a. Beam-line. The line indicating the intersection of the top of the beams with the frames of the ship. b. Bearding-line. The trace of the inner surface of the ship's skin upon the keel, stem, and stern-post. c. Boundary-line. The trace of the outside surface of the skin, corresponding to the outside edge of the rabbet. d. Bow and buttock lines are the boundaries of the vertical sections of the ship, in planes parallel to the vertical longitudinal section. e. Center-line. The central, vertical, longitudinal section. f. The cutting-down line is a curve on the sheer plan, corresponding to the upper surface of the throats of the floors amidships and to the under side of the keelson. g. Diagonal lines show the boundaries of various sections formed by planes which are oblique to the vertical, longitudinal plane, and which intersect that plane in straight lines parallel to the keel. h. Level lines are similar to the water lines, excepting that they are parallel to the keel instead of to the surface of the water, or the line of flotation. i. The main-breadth line is the boundary of the widest part of the ship in each of the three plans, — the shear-plan, half-breadth plan, body-plan. j. Ribbaud-line. An oblique longitudinal section. See Diagonal line. k. Sheer-line. The line of the deck at the side of the ship. The upward curvature towards the ends is called the sheer, and the effect is to raise the vessel to a greater hight out of the water at the stem and stern, where her motion relatively to the water is greatest. l. Stepping-line. The bearding-line at the points where it curves upward towards the ends of the vessel. m. The top-breadth or top-timber line is a line drawn to the sheer of the ship, fore and aft, at the hight of the under side of the gunwale amidships. n. The top-side line is a sheer-line drawn above the top-timber line at the upper side of the gunwale. o. Water-lines are straight and horizontal in the sheer-plan and curved in the half-breadth plan. They show the form of the ship at successive depths, as would appear by so many horizontal sections.
8. (Nautical.) a. A running cord or rope; as, bowline, bunt line, clew line, spilling line, etc. b. A cord for a specific purpose; as, a hand-line, a 20-fathom sounding-line having a lead of from 7 to 14 pounds (see hand-line). A deep-sea line, one of say 200 fathoms, and having a lead of 28 pounds weight (see deep-sea line). A fishing-line. c. A grade of rope, such as marline, white line, tarred line, etc.
9. (Mining.) a. Line of bearing. The strike of a stratum, or its direction at right angles to the dip. b. Synclinal line. The axis of the valley curvature of strata, opposed to anticlinal. c. Anticlinal line. The axis of the ridge or saddle curvature of strata, opposed to synclinal. d. Line of least resistance. The line of mine or axis of explosion. A line drawn from the focus of a mine to that point in the direction of which the charge meets with the least resistance.
10. (Architecture.) Springing line. The line from which an arch rises, and from which the versed sine is calculated.
11. (Masonry.) The bricklayer's cord, which is his guide for level and direction. It is stretched between line-pins.
12. (Railroad-engineering.) A railway-track, as [1322] the main line or trunk. A loop-line, a connecting line, a crossing line, a side line or switch.
13. (Telegraphy.) The wire connecting one station with another. The part of an instrument to which the line is connected is known as its terminal. The wires and instruments form the circuit. See circuit ; wire.
14. (Surveying.) a. Base-line. A carefully measured line which extends between two stations and forms the basis of triangulation. b. Line of direction. The bearing. The line laid down or protracted in a survey.
15. (Drafting and Perspective.) a. The ground line or fanlamental line. The common section of the ground plane and the base of the picture. The terrestrial line. b. The horizontal line. The common section of the horizontal and that of the draft of representation, passing through the principal points. c. The visual line. The line conceived to proceed from the object to the eye. d. The principal line. A line drawn from the eye perpendicular to the picture. The line of distance.
16. (Carpentry.) To strike a straight line on timber or boards; usually a chalk line between points determined by measurement.
