COMMODORE, chef d’ escadre, a general officer in the British marine, invested with the command of a detachment of ships of war destined on any particular enterprise; during which time he bears the rank of brigadier-general in the army, and is distinguished from the inferior ships of his squadron by a broad red pendant tapering towards the outer-end, and sometimes forked. The word is corrupted from the Spanish comendador.
Commodore is also a name given to some select ship in a fleet of merchantmen, who leads the van in time of war, and carries a light in his top, to conduct the rest and keep them together.
COMPANION, a sort of wooden porch placed over the entrance or stair case of the master’s cabin in a merchant-ship.
COMPANY, the whole crew of any ship, including her officers.
COMPASS, an instrument employed to determine the ship’s course at sea, and consisting of a card and two boxes. The card, which is calculated to represent the horizon, is a circle divided into thirty-two equal parts, by lines drawn from the center to the circumference, called points or rumbs. The intervals between the points are also subdivided into equal parts called degrees, 360 of which complete the circle; and consequently the distance or angle comprehended between any two rumbs is equal to 11°, 15´ The four principal rumbs are called the cardinal points, deriving their names from the places to which they tend; viz. the two which extend themselves under the meridian, opposite to each other, pointing to the north and south, are called the north and south points. That which is towards the right hand as we look north is termed east, and its opposite the west point. The names of all the inferior ones are compounded of these, according to their situation. Along the north and south-line is fixed a steel needle, which being touched by the load-stone acquires a certain virtue that makes it hang nearly in the plane of the meridian, and consequently determine the direction of the other points toward the horizon.
The compass being of the utmost importance to the purposes of navigation, it is reasonable to expect that the greatest attention should be used in its construction, and every attempt to improve it carefully examined, and adopted, if proper. Great errors and irregularities, however, have been found incident to the construction of common compasses, arising from the shape of their needles, by which they have not only turned from the true direction, but from that of each other[[6]]. To remedy these inconveniencies, the learned Dr. Knight was induced to contrive a new sea-compass, which is now used aboard all our vessels of war[[7]]. The needles of the other instruments were generally composed of two pieces of steel wire, bent in the middle, and approaching each other towards the ends, where they met. Others were made of one piece of steel of a spring temper, and broad towards the ends, but tapering towards the middle; but the needle in Dr. Knight’s compass is quite straight, and square at the ends, and consequently has only two poles, although the curves are a little confused about the hole in the middle. Needles of this construction, after vibrating a long time, will always point exactly in the same direction; and if drawn ever so little on one side, will return to it again, without any sensible difference.
In order to illustrate the above description, we have exhibited a view of the several parts of the compass, plate [II]. where fig. 19, is the card, with the needle N S, and its cap fixed upon it.
Fig. 21, is the pedestal that supports the card, containing a sewing needle fixed in two small grooves to receive it, by means of a collet C, in the manner of a port crayon. D, the stem, is filed into an octogon, that it may the more easily be unscrewed.
A B, fig. 20, is the box in which the compass hangs in the binacle.
C D, is the ring that supports the inner box.