s a
promise of more to follow.

This planet had been seen five times by Flamsteed before its character
was determined--once nearly a century before--and eight times by
Le Monnier. These names, which might easily have been associated
with a grand discovery, are associated with careless observation.
Eyes were made not only to be kept open, but to have minds behind
them to interpret their visions. Herschel thought he discovered six
moons belonging to Uranus, but subsequent investigation has limited
the number to four. Two of these are seen with great difficulty by
the most powerful telescopes.

If the plane of our moon's orbit were tipped up to a greater
inclination, revolving it on the line of nodes as an axis until
it was turned 85 deg., the moon, still continuing on its orbit in that
plane, would go over the poles instead of about the equator, and
would go back to its old path when the plane was revolved 180 deg.;
but its revolution would now be from east to west, or [Page 175]
retrograde. The plane of the moons of Uranus has been thus inclined
till it has passed 10 deg. beyond the pole, and the moons' motions are
retrograde as regards other known celestial movements. How Uranus
itself revolves is not known. There are more worlds to conquer.

NEPTUNE.

God of the sea; sign [Symbol], his trident.

DISTANCE FROM THE SUN, 2,775,000,000 MILES. DIAMETER, 34,500 MILES.
VELOCITY PER MINUTE, 201.6 MILES. AXIAL REVOLUTION UNKNOWN. ORBITAL,
164.78 YEARS. ONE MOON.

Men sought for Neptune as the heroes sought the golden fleece.
The place of Uranus had been mapped for nearly one hundred years
by these accidental observations. On applying the law of universal
gravitation, a slight discrepancy was found between its computed
place and its observed place. This discrepancy was exceedingly
slight. In 1830 it was only 20"; in 1840,190"; in 1884, 2'. Two
stars that were 2' apart would appear as one to the keenest unaided
eye, but such an error must not exist in astronomy. Years of work
were given to its correction. Mr. John C. Adams, of Cambridge,
England, finding that the attraction of a planet exterior to Uranus
would account for its irregularities, computed the place of such
a hypothetical body with singular exactness in October, 1841; but
neither he nor the royal astronomer Airy looked for it. Another
opportunity for immortality was heedlessly neglected. Meanwhile,
M. Leverrier, of Paris, was working at the same problem. In