not loose and wandering,
and the mere plaything of fortuitous forces, as the atmosphere is
supposed to be; but, on the contrary, has close and most sympathetic
adjustment with the earth-force; and that _it_ is the invisible hand
that holds and manages the grosser atmospheric matter; since we know
this, we are now brought to the study of a great cosmical system.

FOOTNOTES:

[13] Appendix, p. 105.

CHAPTER X.

SUN-SPOTS.

_Grave Doubts._

HERBERT SPENCER says: "At present none of the interpretations of the
sun-spots can be regarded as established."

How numerous and how strange have been the theories promulgated as to
the character of the manifestations called sun-spots. The dark spots in
the sun have been supposed to be "solid bodies revolving very near its
surface," "Smoke of volcanoes;" "Scum floating upon an ocean of fluid
matter;" "Clouds;" "Opaque masses floating in the fluid matter of the
sun, dipping down occasionally," "Fiery liquid surrounding the sun
which, by its ebbing and flowing, the highest parts of it were
occasionally uncovered, and appeared under the shape of dark spots, and
by the return of the fiery liquid, they were again covered, and in a
manner successively assumed different phases;" "Interruptions of
continuity in the bright envelopes immediately surrounding the sun,"
"Cavities" etc.

_Overestimate of the Degree of Spot-shadow._

Public sentiment in regard to the degree of darkness which is disclosed
in sun-spots is exceedingly erroneous. It is believed that the spots are
really dark. ZOeLLNER, however, states that "The black umbra of a spot
emits four thousand times as much light as that derived from an equal
area of the moon." "The blackest part of the spot is intrinsically
bright."

_What They are not, and what They are._

These phenomena may not arise from disruptions taking place on the sun's
surface, neither from violent agitations near that surface. The
essential and intimate character of the so-called sun-spots may be found
in the interruptions of continuity in the fluid occupying the solar
cone-space. This fluid which we call sunlight intercommunicates between
the entire opposing surface of sun and earth, unless interrupted by some
temporary cause. Any cause which is capable of producing results of
such character and magnitude can only act by mor