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Show IS THE MJN GUOn ISO COM).' l E CAX MIT rilOVE. IT IS, XOTWITII- feTAT)!0 OIILAT C1IAMJE3 IV CLIMATE. We want to know whetherlhesun IsshuwiugauysymttomB of decay, says theStry of the Jleaeau. Are the days as warm and bright as tbty were ten J ears ago, one hundred years ago? We cau find no ev-l deuce of any change since tho be-l ginning of authentic records. If the sun's heat had peiciplil Iy cliaugeJ within the last ,000 Jtars w e should expect to find et.rresjond-lug et.rresjond-lug changes In the distribution of plants and animals but no such changes hat e been detected. Tin re la no reason to think that the climate of ancient (Jreece or ancient an-cient Rome was appreciably dlfler ent from the climates of the Greet e and the Rome that we know at this day. The a ine and oln e now grew where they grew ISsk) ears ngo. We must not, however, lay too ouch stress ou tins argument, for the t fleets ot slight changes in the sun's heat may hs.ve been neutralized neutral-ized by (orrispouding adaptation in the pliable organisms of cultivated plants. All we can certainly conclude I that no marked change has taken place In the heat of the sun during historical time. Rut when we come to look back into tiie vastly earlier ages wu II ud tiie most copious evidence evi-dence that tiie earth has undergone great thanges iu climate. Geological records can on this question hardly be mMnterj rtted. Vet it is custom to note that tbtse changes are hardly such as could arise front the gradual exhaustion of the sun's radiation. No doubt In ery early times we have evidence that the earth' climate, clim-ate, must have been much w armer than now. We had the great carboniferous carbon-iferous epoch, w hen the teinirature must almost have t-eeli tropical 111 Arctic latitudes. Yet It Is hardly possible to cite this as evidence that the sun was then much more jiower-ful, jiower-ful, for we are Immediately reminded re-minded of the glacial epoch when our temperate zones were etirased in sheets of solid Ice, as northim Greenland Is at present. If we sup-lose sup-lose the sun to hate been holler than it is at present to account for the vegetation which produced coal, then we ought to assume the sun to be colder than it Is now to account for the glacial epoch. It Is not reasonable rea-sonable to attributesuch phenomena to sucit oscillations In the radiation from tbe sun. The glacial c-poens prove that we can not apieal to geology in aid of the doctrine that a secular cooling of the sun is now in progress. The geological variations of climate cli-mate may hate Iieeu caused b cuingts in the earth itself, hi changes in the iositiou of its axis, by changes in its actual orbit; but. however they have lieen cauMd, they hardly tell us much with re-gird re-gird to the previous history of the sun. The heat of tho sun has lasted for countless ageit, yet wo cannot credit the sun witli the power of of actually creating heat. We must apply e en to the majestic mass of the sun the same laws which we hive found by our experiments ou the earth. We must ask: Whence comes the hesit sufficient to supply this tremendous outgoing? |