many of the perturbations in our great solar family. Now during regular
observations of the position of Uranus in space, some inexplicable
irregularities were soon perceived. The astronomers having full faith in
the universality of the law of attraction, could not do otherwise than
attribute these irregularities to the influence of some unknown planet
situated even farther off. But at what distance?

A very simple proportion, known as Bode's law, has been observed, which
indicates approximately the relative distances of the planets from the
Sun. It is as follows: Starting from 0, write the number 3, and double
successively,

0 3 6 12 24 48 96 192 384.

Then, add the number 4 to each of the preceding figures, which gives the
following series:

4 7 10 16 28 52 100 196 388.

Now it is a very curious fact that if the distance between the Earth and
the Sun be represented by 10, the figure 4 represents the orbit of
Mercury, 7 that of Venus, 16 of Mars; the figure 28 stands for the
medium distance of the minor planets; the distances of Jupiter, Saturn,
and Uranus agree with 52, 100, and 196.

The immortal French mathematician Le Verrier, who pursued the solution
of the Uranian problem, supposed naturally that the disturbing planet
must be at the distance of 388, and made his calculations accordingly.
Its direction in the Heavens was indicated by the form of the
disturbances; the orbit of Uranus bulging, as it were, on the side of
the disturbing factor.

On August 31, 1846, Le Verrier announced the position of the
ultra-Uranian planet, and on September 23d following, a German
astronomer, Galle, at the Observatory of Berlin, who had just received
this intelligence, pointed his telescope toward the quarter of the
Heavens designated, and, in fact, attested the presence of the new orb.
Without quitting his study table, Le Verrier, by the sole use of
mathematics, had detected, and, as it were, touched at pen's point the
mysterious stranger.

Only, it is proved by observation and calculation that it is less remote
than was expected from the preceding law, for it gravitates at a
distance of 300, given that from the Earth to the Sun as 10.

This planet was called Neptune, god of the seas, son of Saturn, brother
of Jupiter. The name is well chosen, since the King of the Ocean lives
in darkness in the depths of the sea, and Le Verrier's orb is also
plunged in the semi-obscurity of the depths