ECLIPSE. An obscuration of a heavenly body by the interposition of another, or during its passage through the shadow of a larger body. An _eclipse of the sun_ is caused by the dark body of the moon passing between it and the earth. When the moon's diameter exceeds the sun's, and their centres nearly coincide, a _total eclipse_ of the sun takes place; but if the moon's diameter be less, then the eclipse is _annular_. ECLIPTIC. The great circle of the heavens which the sun appears to us to describe in the course of a year, in consequence of the earth's motion round that luminary. It is inclined to the equinoctial at an angle of nearly 23° 28′, called the obliquity of the ecliptic, and cuts it in two points diametrically opposite to each other, called the equinoctial points. The time when the sun enters each of these points (which occurs about the 20th of March and 23d of September, respectively) is termed the equinox, day and night being then equal; at these periods, especially about the time of the vernal equinox, storms, called the equinoctial gales, are prevalent in many parts of the globe. The two points of the ecliptic, which are each 90° distant from the equinoctial points, are called the solstitial points. That great circle which passes through the equinoctial points and the poles of the earth, is called the equinoctial colure; and that which passes through the solstitial points and the poles of the earth, the solstitial colure. ECLIPTIC CONJUNCTION. Is the moon in conjunction with the sun at the time of new moon, both luminaries having then the same longitude, or right ascension. ECLIPTIC LIMITS. Certain limits of latitude within which eclipses take place, and beyond which they cannot occur. ECONOMY. A term expressive of the system and internal arrangement pursued in a ship. EDDY. Sometimes used for the dead-water under a ship's counter. Also, the water that by some interruption in its course, runs contrary to the direction of the tide or current, and appears like the motion of a whirlpool. Eddies in the sea not unfrequently extend their influence to a great distance, and are then merely regarded as contrary or revolving currents. It is the back-curl of the water to fill a space or vacuum formed sometimes by the faulty build of a vessel, having the after-body fuller than the fore, which therefore impedes her motion. It also occurs immediately after a tide passes a strait, where the volume of water spreads suddenly out, and curves back to the edges. The Chinese pilots call eddies, chow-chow water. EDDY-TIDE. When the water runs back from some obstacle to the free passage of the stream.