IN-BOARD. Within the ship; the opposite of out-board.
IN-BOATS! The order to hoist the boats in-board.
IN-BOW! The order to the bowman to throw in his oar, and prepare his boat-hook, previous to getting alongside.
INCH. The smallest lineal measure to which a name is given; but it has many subdivisions. Also, a general name for a small coast islet on the northern shores, from the old Gaelic word.
INCIDENCE, Angle of. That which the direction of a ray of light, &c., makes at the point where it strikes with a line drawn perpendicularly to the surface of that body.
INCLINATION. In geometry, is the mutual tendency of two lines or planes towards each other, so as to form an angle.
INCLINATION OF AN ORBIT. The angle which the path of a comet or planet makes with the plane of the ecliptic.
INCLINATORY NEEDLE. An old term for the [dipping-needle] (which see).
INCLINOMETER. An invention by Wales in Cook's second voyage, where particulars are given.
INCOMPETENCY, or Insufficiency, of a Merchantman's Crew. A bar to any claim on warrantry; as it is an implied condition in the sea-worthiness of a ship, that at sailing she must have a master of competent skill, and a crew sufficient to navigate her on the voyage.