hanges, but Faith with the knowledge of Him that
abideth for ever, and it is to this higher knowledge that St. James
wished to point his readers.
Science deals with the knowledge of things that change, as they change
and of their changes. The physical facts that we have learned in the
last years about that changeful body the sun are briefly these:--
Its core or inner nucleus is not accessible to observation, its nature
and constitution being a mere matter of inference. The "photosphere" is
a shell of incandescent cloud surrounding the nucleus, but the depth, or
thickness of this shell is quite unknown. The outer surface--which we
see--of the photosphere is certainly pretty sharply defined, though very
irregular, rising at points into whiter aggregations, called "faculae,"
and perhaps depressed at other places in the dark "spots." Immediately
above the photosphere lies the "reversing layer" in which are found the
substances which give rise to the gaps in the sun's spectrum--the
Fraunhofer lines. Above the "reversing layer" lies the scarlet
"chromosphere" with "prominences" of various forms and dimensions rising
high above the solar surface; and over, and embracing all, is the
"corona," with its mysterious petal-like forms and rod-like rays.
The great body of the sun is gaseous, though it is impossible for us to
conceive of the condition of the gaseous core, subjected, as it is, at
once to temperature and pressure both enormously great. Probably it is a
gas so viscous that it would resist motion as pitch or putty does. Nor
do we know much of the nature of either the sun-spots or the solar
corona. Both seem to be produced by causes which lie within the sun;
both undergo changes that are periodical and connected with each other.
They exercise some influence upon the earth's magnetism, but whether
this influence extends to terrestrial weather, to rainfall and storms,
is still a matter of controversy.
The sun itself is distant from the earth in the mean, about 92,885,000
miles, but this distance varies between January and June by 3,100,000
miles. The diameter of the sun is 866,400 miles, but perhaps this is
variable to the extent of some hundreds of miles. It would contain
1,305,000 times the bulk of the earth, but its mean density is but
one-quarter that of the earth. The force of gravity at its surface is
27-1/2 times that at the surface of the earth, and it rotates on its
axis in about 25 days. But the sun's surface
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