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a flight of erupted globules (gathering probably into a single mass as they travelled onwards) came into direct contact with the earth, that face of the Earth turned at the moment towards the Sun must necessarily be the scene of the encounter. Now, as a matter of fact, it has been observed that more aerolites fall near noon than at any other hour. We have this on the authority of Humboldt, a careful student of the subject of meteoric astronomy, and the fact is confirmed by the systematic researches of Alex. Herschel, Heis, and others in our own time.

Now as to the second case, the point to be chiefly noticed is this: that if our Sun sends forth such missiles towards the domains of other suns, analogy should guide us to the conclusion that those other suns—the stars-must also, from time to time, eject metallic matter from their substance. If this is so, we might expect that some of the meteors which reach our Earth would afford some indications of their stellar origin.

For example, their velocity might be in excess of that due to the Sun's attracting influence (see p. 87); in which case no explanation would be so plausible as the very conclusion towards which we are now being forced. But here again, as a matter of fact, the most careful observers, Alexander Herschel in England, Professor Newton in America, Fr. Secchi in Rome, Heis in Germany, tell us of meteoric velocities of 60, 70, 80, even 90 and 100 miles per second. Such velocities, if real (and it is difficult to question many

of the observations on which these results have been based), correspond exactly with the results to which we have been just led.

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Again, the structure of meteors, if carefully examined, might be expected to reveal evidence of their having once existed within the interior of an orb like our Sun. But Mr. Sorby, so far back as 1864, wrote thus respecting the microscopic examination of certain meteors. The most remote condition of which we have positive evidence, was that of small detached melted globules, the formation of which cannot be explained in a satisfactory manner, except by supposing that their constituents were originally in the state of vapour as they exist in the Sun.' He found evidence that the meteors had been in the state of vapour while under enormous pressure, and in mountain masses.'

Yet again, the chemical structure of meteors might be expected to supply evidence of a stellar origin. Now, the late Professor Graham, after a careful analysis of the Lenarto meteor, reasons thus:-It has been found difficult to impregnate malleable iron with more than an equal volume of hydrogen under the pressure of our atmosphere.' Now, 'the meteoric iron (this Lenarto iron is remarkably pure and malleable) gave up almost three times that amount without being fully exhausted. The inference is, that the meteorite had been extruded from a dense atmosphere of hydrogen gas, for which we must look beyond the light cometary matter floating about within the limits of our own

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system. . Hydrogen has been recognised in the spectrum analysis of the light of the fixed stars by Messrs. Huggins and Miller. The same gas constitutes, according to the researches of Fr. Secchi, the principal element of a numerous class of stars, of which a Lyræ is the type. The iron of Lenarto has no doubt come from such an atmosphere in which hydrogen greatly prevailed. This meteorite may be looked upon as holding imprisoned within it, and bearing to us, the hydrogen of the stars.'*

I would further invite the attention of the reader to the account of the behaviour of sun-spots and faculæ (see pp. 216, 217); to Gilman's account of the aspect of a large prominence (p. 307), and to the reasoning on the striations observed by him (pp. 378, 379); and, lastly, to Zöllner's account of linear flashes in the spectrum (p. 307). All these matters bear very pertinently, as it seems to me, on the theory we are now considering; and they acquire fresh force from the fact, that they have not been introduced here for the purpose of supporting the theory, but appeared in the first edition of this work, in which the theory was not advocated.

Even the perplexing relation considered at p. 218, may find an explanation in the theory now under discussion. For regarding the spots as phenomena of eruption, that is, as beginning with eruption, we might

* See further The Fuel of the Sun,' by Mr. W. Mattieu Williams, F.C.S., in which the theory of the expulsion of matter from the Sun is ably advocated. Some of his inferences are not in accordance with strict dynamical principles; but the book is well worth careful reading.

expect that their occurrence would be associated with the planetary motions of recess or approach. Eruptions and earthquakes on our own earth, stable as is its substance by comparison with the Sun's, occur more frequently when the moon is in perigee; and Sir John Herschel has explained the predominance of active volcanic and earthquake regions along shore-lines, as depending on the seemingly insignificant changes due to tidal action. How much more, therefore, might we expect that the solar equilibrium would be disturbed by planetary action, when all that has been revealed respecting the Sun tends to show that the mightiest cenceivable forces are always at work beneath his photosphere, one or other needing only (it may well be) the minutest assistance from without to gain a temporary mastery over its rivals. And if, as recent observations tend to show, the mightiest of the planets sympathises with solar action-if when the Sun is most disturbed, the belts of Jupiter are also subject (as of late, and in 1860) to strange phenomena of change-how readily do we find an explanation of what would otherwise seem so mysterious, when we remember that as Jupiter disturbs the mighty mass of the Sun, so the Sun would reciprocally disturb the mass of the largest of his attendant orbs.

The reasoning which has led to the suggestion that electrical processes are at work in producing a portion of the coronal light, as well as that which has seemed to many acute minds to support the theory of an atmosphere of extreme tenuity, extending millions of

miles from the Sun, would appear to be confirmed by, and to confirm the arguments for the emission theory. For electrical action could not be excited where the coronal streamers are seen, save by the rush of matter projected radially from the Sun through a medium resembling an atmosphere.

Furthermore, the meteoric theory advocated abovea theory quite distinct from that of a meteor-generating emission-need by no means be abandoned, if the emission theory is regarded as established. It will remain for future observations to determine what proportion of the coronal light is due to the several causes here considered; but it can scarcely be doubted that an appreciable proportion of that light is due to each.

The study of the corona has thus led us to conclusions involving relations of cosmical importance. We have been led to associate the corona with the scheme of meteoric systems, and therefore with the mysterious phenomena presented by comets. We have evidence also associating the solar corona with coronæ surrounding the millions on millions of suns scattered throughout space. In studying the processes which thus seem to be at work, we are led to consider their bearing as well on the past as on the future of the universe of solar systems. A new bond of association is recognised between these uncounted millions of systems. Already light has brought its message from the star depths surrounding us on all sides; and we have learned to believe that the light

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