This page has been validated.
THE GUIDING-NEEDLE ON AN IRON SHIP.
305
This force is resolvable into two others, the horizontal S H, and the vertical S Z; and the former is further divisible into S B, parallel to the midship line, and B H, transverse to it.
The magnetic power of the bar is thus resolved parallel to the
Fig. 15.—The Magnetic Forces of a Ship concentrated in Three Planes.
three co-ordinate axes. Almost all the structural iron of the ship—beams, knees, engines, boilers, etc.—is symmetrically arranged with reference to the vertical plane through the keel; so that for a piece T, on the starboard side, we should generally find another similarly disposed on the port side.
