ances.
CENTRIFUGAL FORCE (_centre fleeing_).
CHROMOLITHIC PLATE of spectra of metals, to face 50.
CIRCUMPOLAR STARS, map of north, 201.
COLORS OF STARS, 214.
COLURES, the four principal meridians of the celestial sphere
passing from the pole, one through each equinox, and one through
each solstice.
COMETS, 126; Halley's, 128; Biela's lost, 129; Encke's, 130;
constitution of, 131; will they strike the earth? 133.
CONJUNCTION. Two or more bodies are in conjunction when they
are in a straight line (disregarding inclination of orbit) with the
sun. Planets nearer the sun than the earth are in inferior
conjunction when they are between the earth and the sun; superior
conjunction when they are beyond the sun.
CONSTELLATION, a group of stars supposed to represent some figure:
circumpolar, 201; equatorial, for December, 202; for January, 203;
April, 204; June, 205; September, 206; November, 207; southern
circumpolar, 208.
CULMINATION, the passage of a heavenly body across the meridian
or south point of a place; it is the highest point reached in its
path.
CUSP, the extremities of the crescent form of the moon or an
interior planet.
DECLINATION, the angular distance of a celestial body north or south
from the celestial equator.
DEGREE, the 1/360 part of a circle.
DIRECT MOTION, a motion from west to east among stars.
DISK, the visible surface of sun, moon, or planets.
DISTANCE OF STARS, 70.
DOUBLE STARS, 210.
EARTH, revolution of, 109; in space, 142; irregular figure, 145.
ECCENTRICITY OF AN ELLIPSE, the distance of either focus from centre
divided by half the major axis.
ECLIPSE (_a disappearance_), 157.
ECLIPTIC, the apparent annual path of the sun among the stars;
plane of, 106.
EGRESS, the passing of one body off the disk of another.
ELEMENTS, the quantities which determine the motion of a planet:
data for predicting astronomical phenomena; table of solar, 274.
ELEMENTS, chemical, present in the sun, 270.
ELONGATION, the angular distance of a planet from the sun.
EMERSION, the reappearance of a body after it has been eclipsed or
occulted by another.
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EQUATOR, terrestrial, the great circle half-way between the poles of
the earth. When the plane of this is extended to the heavens,
the line of contact is called the celestial equator.
EQUINOX, either of the points in which the sun, in its apparent
annual course among the stars, crosses the equator, making days
and