Longitude by Account to Magnetic Azimuth

The meridian of the ship determined by dead reckoning.

The meridian of the ship determined by an altitude of a heavenly body and the corresponding time shown by the chronometer.

The meridian of the ship determined by the employment of a traverse table. (See Dead Reckoning.)

The meridian of the vessel determined by observing equal altitudes of the sun--one before and the other after his meridian passage.

The meridian of the vessel determined by an observation of a heavenly body.

The meridian of the vessel determined without the aid of a sextant. In this case no altitude is measured, the limit of the sun being on the horizon.

Longitude expressed in degrees, minutes and seconds of angular measure (deg ' ").

Longitude expressed in hours, minutes and seconds of time (h. m. s.)

A couplet for naming the longitude when working a chronometer altitude sight. It is as follows:

"Greenwich time best, longitude west;

Greenwich time least, longitude east."

(See Gained Day.)

L's of Navigation. (See Part I.)

Parallels near the equator.

(See Part I.)

The passage (transit) of the sun, moon, planets and stars over the meridian 180 deg. from the upper transit.

Same as Lubbers' Point.

(See Part I).

Pertaining to the moon.

The angular distance of the moon's centre from certain other heavenly bodies.

The variation in the moon's motion.

An observation of the moon; the angular distance of the moon from another heavenly body, the altitudes of each, and the chronometer time of observation the data for calculating the longitude.

The period between two successive new moons; the lunar month; the synodical period.

Combining the revolutions of the sun and moon.

The period after which the eclipses return in the same order--532 years.

The interval of time existing between the moon's transit and the next following high water.

A double reflecting instrument employed for measuring the distance of inaccessible objects.

Dark sports on the face of the sun.

Star clusters near the south pole of the heavens.

A substance which attracts iron.

A natural magnet is an ore, generally of a gray color, and consisting principally of oxides of iron and a small portion of quartz and alumina.

An artificial magnet is a bar, such as a compass needle, or a mass of iron or steel, to which magnetic force has been imparted by direct contact with a magnetic body, such as an artificial magnet in the shape of a horse-shoe, or by a dynamo.

The bearing by compass of a heavenly body at rising and setting from the east and west points of the heavens--thus we could say the sun's bearing at rising was east 10 deg. north, etc.

The bearing by compass of a heavenly body when above the horizon, from the north or south poles of the heavens--as, for example, the sun bore N. 85 deg. east, etc.