bined. These, by his attractive power, he retains in their
several paths and orbits, and even far distant Neptune acknowledges his
potent sway. With prodigal liberality he dispenses his vast stores of
light and heat, which illumine and vivify the worlds circling around
him, and upon the constant supply of which all animated beings depend
for their existence. Deprived of the light of the Sun, this world would
be enveloped in perpetual darkness, and we should all miserably perish.

The Sun is distant from the Earth about 93,000,000 miles. His diameter
is 867,000 miles, or nearly four times the extent of the radius of the
Moon's orbit. The mass of the orb exceeds that of the Earth 330,000
times, and in volume 1,305,000 times. The Sun is a sphere, and rotates
on his axis from west to east in 25 days 8 hours. The velocity of a
point at the solar equator is 4,407 miles an hour. The density of the
Sun is only one-fourth that of the Earth, or, in other words, bulk for
bulk, the Earth is four times heavier than the Sun. The force of gravity
at the Sun's surface is twenty-seven times greater than it is on the
Earth; it would therefore be impossible for beings constituted as we are
to exist on the solar surface.

The dazzling luminous envelope which indicates to the naked eye the
boundary of the solar disc is called the PHOTOSPHERE. It is most
brilliant at the centre of the Sun, and diminishes in brightness towards
the circumference, where its luminosity is but one-fourth that of the
central portion of the disc. The photosphere consists of gaseous vapours
or clouds, of irregular form and size, separated by less brilliant
interstices, and glowing white with the heat derived from the interior
of the Sun. In the telescope the photosphere is not of uniform
brilliancy, but presents a mottled or granular appearance, an effect
created by the intermixture of spaces of unequal brightness. Small
nodules of intense brilliance, resembling 'rice-grains,' but which,
according to Nasmyth, are of a willow-leaf shape with pointed
extremities, which form a network over portions of the photosphere, are
sprinkled profusely over a more faintly luminous background. These
'grains' consist of irregular rounded masses, having an area of several
hundred miles. By the application of a high magnifying power they can be
resolved into 'granules'--minute luminous dots which constitute
one-fifth of the Sun's surface and emit three-fourths of the light. This
gra