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system had its birth. Tracing back the history of that system, we seem to recognise a time when the sun's supremacy was still incomplete, when the planets struggled with him for the continually inrushing materials from which his substance as well as theirs was to be recruited. We see him clearing, by the mighty energy of his attraction, a wide space around him of all save such relatively tiny orbs as Venus and the Earth, Mars, Mercury, and the asteroids. With more distant planets the struggle was less unequal. The masses which flowed in towards the centre of the scheme swept with comparatively slow motion past its outer bounds, so that the subordinate centres there forming were able to grasp a goodly proportion of material to increase their own mass or to form subordinate systems around them. And so the planets, Jupiter and Saturn, Uranus and distant Neptune, grew to their giant dimensions, and became records at once of the sun's might as a ruler-for without his overruling attraction the material which formed these planets would never have approached the system-and of the richness of the chaos of matter from which his bulk and theirs was alike derived. Nor is the consideration without a mysterious attraction, that in thus looking back at the past history of our system, we have passed, after all, but a step towards that primal state whence the conflict of matter arose. We are looking into a vast abysm, and, as we look, fancy we recognise strange movements and signs, as if the depths were shaping themselves into definite forms. But in truth those movements show only the vastness of the abysm; those depths speak to us of far mightier depths, within which they are taking shape. 'Lo! these are but a portion of His ways; they utter but a whisper of His glory.'"1

Truth is stranger than fiction and excels romance. Many ages back, in the immeasurable swoop of the past, an enormous moving mass existed and collided at and around the place now occupied by the solar system. This mass, obtaining swift and vehement rotation, assumed a somewhat globular shape. Huge rings of matter were integrated during successive ages of spinning and revolving-so were the planets formed. These again broke into portions-so are satellites

"The Sun" R. A. Proctor.

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accounted for-while certain whiffs or puffs gave birth to some of the eccentric comets. Many of the meteorite systems still visit us, although they belong to the great primary mass. The array of sun and planets, the pomp of all material worlds, are a procession and gathering from the unseen to the seen, out of infinite to finite space. Their duration, compared with eternity, is as the flight of birds into our horizon-to pass out again and be no more seen.

The Sun's Age.

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It has never been maintained that the matter of the sun was created or even organised on the fourth day." Theologians hold that the development of the solar system includes all terrestrial arrangements. The formation and operation of the sun and of the earth were co-ordinate and partly contemporaneous. The sun, the earth, and other planets, being for one another, their whole substance formed part of that universal cosmical arrangement which is described Genesis i. 1. Dr. Buckland, p. 27, "Bridgewater Treatise," observes-"We are not told that the substance of the sun and moon was first called into existence on the fourth day. The text may equally imply that those bodies were then prepared and appointed to certain offices of high importance to mankind, to give light upon the earth, and to rule over the day and over the night, to be for signs, and for seasons, and for days, and for years. The fact of their creation had been stated before in the first verse."

Against this it may be urged-"The text says the sun was made on the fourth day, not made to appear. Just as God made the firmament, made the beast of the earth, made man, so did He make two great lights and the stars. There is an end of all ingenuousness in interpreting Scripture, if we foist in one of these examples a meaning not borne in any of the others." The reply is simple and convincing-The word made" is not to be strained in the least, and when we say it means, not the making of globular and opaque masses in the depths of space, but the making of visible lights as they appear moving in the sky, that meaning is correct and natural. If, moreover, our science is correct as to the progressive con"Genesis," p. 151: Prof. Lange.

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densation of the sun, the luminous atmosphere would be cleared gradually during the sun's process of integration as a revolving light. The development of the earth is an analogue of the development of suns and stars. As the earth condensed, so the sun condenses. One theory supposes the condensation of the sun and planets from a nebulous mass, whatever that may mean; and the condensation of the sun from the original mass can be calculated. Professor Helmholtz gives a formula.1 Work of condensation. M -g. The mass of the sun is M, the mass of the earth is m; the sun's radius is R, the earth's radius is r. Taking M=4230×1027 lbs., m=11,920 lbs., R=2,328,500,000 feet, and r=20,889,272 feet, we have for the total work performed by gravitation in foot-pounds—

Work

3. (20,889,272*5)2 × (4230 × 1027)2

R m

5 2,328,500,000 x 11,920 X 1021 = 168,790 x 1036 foot-pounds. The heat, thus produced, would suffice for 20,237,500 years; and the quantity of heat given out, which previously existed as original temperature, was 49,850,000 years' heat; making in all 70,087,500 years' heat. This represents the total amount of heat given out since the mass began to condense. Mr. Croll says "Let us assume that by the time that the mass of the sun had condensed to within the space encircled by the orbit of the planet Mercury (that is, to a space having, say, a radius of 18,000,000 miles) the earth's crust began to form; and let this be the time when the geological history of our globe dates its commencement. The total amount of heat generated by the condensation of the sun's mass from a sphere of this size to its present volume would equal 19,740,000 years' sun-heat. The amount of original heat given out during that time would equal 48,625,000 years' sun-heat, thus giving a total of 68,365,000 years' sun-heat enjoyed by our globe since that period." If the sun's gravity is greatly increased at the centre, the quantity will be considerably more; but there is no warrant for anything like the

1 "Phil. Mag." sect. 4, vol. xi. p. 76 (1856). Also in "Climate and Time," p. 348 James Croll.

2 "Climate and Time," p. 352: James Croll.

Sun's Physical Constitution.

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period demanded by some geologists, and the general conclusion arrived at by measurement of the sun's heat is that one hundred millions of years amply suffice for condensation of the nebulous mass into the present form.

A process of condensation has not only taken place in the sun, but in all members of the solar system. There has been advance, if the generally received hypothesis be true, in every one from the gaseous to the liquid, from the liquid to the solid state, to be followed by extinction of their light. There was a time when the sun did not give light in the manner now given; a time when the earth, even if light were given, could not behold it; a time when all the visible glory was invisible; a time when Nature, as now known, was not; in a Source beyond Nature is Nature's origin to be found. Worlds precede worlds in time, worlds lie beyond worlds in space.

Turn to the account-" God made two great lights; the greater light to rule the day, and the lesser light to rule the night: He made the stars also. And God set them in the firmament of the heaven to give light upon the earth." The stars seem mentioned lest they should be accounted uncreated. Sun, moon, stars, are classed according to their apparent magnitude and importance. The word "made" is more formative than the word "create." It is used for "dressing," "arranging," "making ready." The calf was dressed for Abraham's mysterious visitors, and the cakes were made of meal (Gen. xviii. 6, 7). The same Hebrew word, used for "dressing," "making," "crowning," informs us that the sun was dressed, made, crowned ruler, to give light on the earth. By the time earth and water were separated, and dense vaporous clouds rarefied, the earth's mass attained a measure of consolidation, and began to exhibit vital power in lowest forms of vegetable organisms; the sun, clearing the photosphere, sent rays of light and heat through the vast pressure of his own vapours, and became lord of the day. The Sun's Physical Constitution.

The actual density is about one-fourth that of the earth, or a little greater than the density of water. The tremendous

1 The sun is 1,260,000 times larger than the earth, and 882,000 miles in diameter. More than 1,200,000 earths would be required to form the substance

heat, whatever pressure the gases and vapours are subject to, renders a solid nucleus improbable; and we must regard the sun as, in the main, a gaseous body. Around it is no permanent or solid crust, but an envelope continually pierced by blasts and jets from within. This great mass, swaying our system, is compressed towards the centre, but hardly any definite theories can be adopted concerning any other than its gaseous condition. The attractive and repulsive forces are such, and the elements exist in forms and quantities with which we are so nearly unacquainted, that when one difficulty is removed from our understanding it gives place to another. The sun's envelope cannot, in any ordinary sense, be counted a crust at all; but as the vaporous globe is in the presence of the cold of space, there is necessarily a process on the outer surface corresponding to the formation of clouds in our skies. The vapours composing them are chiefly metallic elements, which condensing may descend in sheets of fire, and form a nearly continuous envelope, through which the central imprisoned gases are erupted with great violence. Mr. Proctor states "The sun is a gigantic bubble whose walls are gradually thickening, and its diameter diminishing, at a rate determined by its loss of heat. It differs, however, from ordinary bubbles in the fact that its skin is continually penetrated by blasts and jets from within." 1

Sir W. Herschel viewed the sun as a solid globe, around which lies an atmosphere of complex nature. He thought that the real body of the sun was neither illuminated nor heated very greatly. "Whatever fanciful poets may say in making the sun the abode of blessed spirits, or angry moralists devise in pointing it out as a fit place for the punishment of of one sun, and the weight or mass is 300,000 times greater than that of the earth. Our sun is not a large star compared with others, for Sirius is equal in bulk to more than 4000 suns. The surface of the sun is about 2,284,000,000,000 square miles, there are 3,097,600 square yards in every square mile, and on every square yard a heat is produced equal to that which would be caused by burning on it six tons of coal an hour. The impact of matter falling into the sun merely from the earth's distance, would give 6000 times the amount of energy which would be produced by mere burning. The sun travels at the rate of 154,185,000 miles the year. His mean distance from the earth is 91,430,000 miles; rotation on the axis occupies about 25.38 days.

"The Sun a Bubble:" R. A. Proctor.

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