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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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