WHAT SHALL I DO?
WHAT shall I do lest life in silence pass?
And if it do,

And never prompt the bray of noisy brass,
What need'st thou rue?

Remember aye the ocean deeps are mute;
The shallows roar ;

THE DIVINE IN THE COMMONPLACE.
AT the moment that Fate had set apart
For their meeting, they met; and from
heart to heart

A bond of sympathy straightway grew,
And one they became, who till then were
two.

Worth is the Ocean-Fame is but the Had you asked his friends to tell you aught

bruit

Along the shore.

What shall I do to be forever known?

Thy duty ever.

Of the kind of fellow the girl had "caught,"
One would have called him "an honest

soul,"

66

Another, a very good sort on the whole,"

This did full many who yet slept un- And all would assure you the man had

known

Oh! never, never!

Think'st thou, perchance, that they remain

unknown

Whom thou know'st not?

naught Of hidden depths, and they couldn't conceive

("But you can't account for a woman's whim!")

By angel-trumps in heaven their praise is Whatever the girl could see in him.

blown

Divine their lot.

What shall I do to gain eternal life?

Discharge aright

Her friends would have answered much the

same

Of the girl henceforward to bear his name: "A plain, little, inoffensive thing,

The simple dues with which each day is Lucky to win a wedding-ring ;

rife;

Yea, with thy might.

Ere perfect scheme of action thou devise
Will life be fled,

While he, who ever acts as conscience cries,
Shall live, though dead.

SCHILLER.

A PURE RIVER OF WATER OF LIFE.
We know not a voice of that River,
If vocal or silent it be,

Where for ever and ever and ever

It flows to no sea.

More deep than the seas is that River,

More full than their manifold tides,
Where for ever and ever and ever
It flows and abides.

Pure gold is the bed of that River,
(The gold of that land is the best),
Where for ever and ever and ever,
It flows on at rest.

Oh, goodly the banks of that River,

Oh, goodly the fruits that they bear,
Where for ever and ever and ever,
It flows and is fair.

For lo! on each bank of that River,

The Tree of Life life-giving grows, Where for ever and ever and ever. The pure River flows.

CHRISTINA G. ROSSETTI.

THE SIGNIFICANCE OF CARBON IN THE

UNIVERSE.

BY SIR ROBERT BALL, F.R.S.

From The Fortnightly Review. of the astronomer at all times when
the sun itself is visible and when the
necessary state of solar activity is
granted. About a quarter of a century
ago the corona was regarded as having
no more than a problematical exist-
ence. It did not then seem certain
that the halo of glory by which the
sun was seen to be surrounded during
the precious moments of a total eclipse
actually pertained to the luminary. It
was sometimes thought that the co-
rona had no real physical existence,
but that it was merely an optical illu-
sion, an effect, in fact, produced by the
diffraction of light round the moon,
when its dark body became interposed
between the observer and the sun.
But the several eclipses which have
happened within the last twenty-five
years have established beyond all ques-
tion the veritable nature of the corona
as a mighty solar appendage. It is
true, that even if we add together the
durations of all the total eclipses which
have happened since the reality of the
corona was admitted, they do not ex-
ceed about half an hour. For not
much more than twenty minutes all
told have astronomers as yet succeeded
in observing this object. However, a
good deal has been learned as to its
nature. Indeed, the minutes and sec-
onds at the disposal of observers dur-
ing a total eclipse are at present almost
exclusively devoted to the corona. No
doubt other phenomena are then vis-
ible, but as they can be seen without
the aid which an eclipse renders, the
attention of the men of science whe
journey to the ends of the earth to see
an eclipse is entirely concentrated on
that particular part of the solar sur-
roundings which can be observed at
present by no other means.
We say

IT not unfrequently happens that a scientific discovery which promises to be both of importance and of interest, fails at the time it is first made to attract the degree of notice to which its merits entitle it and which it is destined ultimately to receive. The announcement may have been duly made, the evidence by which it is supported may have been duly set forth, and yet, for some cause or other, the attention of the public has not been arrested. This may happen, in fact it actually has happened, notwithstanding that the author of the discovery is already known as a competent authority on his subject, and notwithstanding that the scientific society to which he has communicated his discovery is universally recognized as most suitable for such a purpose. Nor are the causes hard to divine why such undeserved obscurity should for a time occasionally befall a new scientific doctrine. The facts announced may be so far in advance of their time that the knowledge requisite for their due appreciation may not be sufficiently widely diffused, even among that part of the community specially interested in such subjects. Every scientific man has, I am sure, often felt that a theory or a discovery, which at some periods in the course of his education he has viewed with indifference, has at other times presented to him so great a charm, that he finds it almost impossible to understand his previous phase of intellectual indifference.

Of late years the study of the sun has received so much attention that our knowledge of the luminary has been greatly advanced. First, there" at present;" but there is some reacame the epoch-making achievement son to hope that before long a scheme of Stokes and Kirchhoff, by which may be devised for the study of this the dark lines in the solar spectrum most delicate solar feature, even dereceived their interpretation. Then spite the dazzling splendor of the disc those solar prominences which were of the sun which hides the feeble raonly to be observed at first on the rare diance of its outer appendages. The occasions of a total eclipse, were, by marvellous success which has attended the ingenious contrivance of Janssen Professor Hale's attempts to obtain and Lockyer, brought within the scope photographs of the solar prominences

and the solar faculæ seems to hold out its important function as a dispenser of

a promise that the endeavors to represent the delicate streamers forming the solar corona may not always be fruitless.

light and heat. It is in Dr. Stoney's paper that the peculiar significance of solar carbon seems to have been first indicated, and all that has since been In the year 1866, a paper was pre-learned with regard to the nature of sented to the Royal Society by the ac- the great luminary tends still further to complished physicist, Dr. G. Johnstone strengthen the force of his reasoning. Stoney, which contained an elaborate To explain this matter with sufficient series of inquiries on the physical na- completeness to make it thoroughly ture of the sun and the stars. It was intelligible, it will be necessary to prewritten in those carly days when mise a few details with respect to the Kirchhoff's prism had no doubt dis- construction of the sun, so far as it is closed the presence of iron and of accessible to us. many other metals and metalloids in The examination of the solar extethe sun, but the great impetus which rior through a telescope does not exsolar discovery has since received had hibit the uniform surface which might then hardly commenced. Eclipses had at first be expected from its appearance not at that time been watched for and to the unaided eye. The surface of the studied with anything like the atten- luminary has clearly a texture, so to tion which is now accorded to them, speak; it is composed of more or less and the public interest in the physics isolated portions, whether we choose of the great luminary, which is now so to call them granules, or willow leaves, remarkable, can then be hardly said to or solar clouds, or by any other term. have existed. This is probably the The so-called spots of which we hear reason why this remarkable paper of so much are seen to be openings from Dr. Stoney's failed at the time to at- which the granules or clouds are, as it tract so much attention as it deserved. were, drawn aside. In some cases the But at the present day there can be no spot appears to be nothing more than longer any doubt of its importance and a glimpse between the circumjacent scientific value. I have certainly no glowing clouds into the comparative intention to enter now into any full gloom of the solar interior. In other discussion of Dr. Stoney's elaborate cases, the presence of the so-called work. This would not be the place for umbra or intermediate part in the insuch an enterprise. There is, how-ner margin of a spot, causes the decline ever, one doctrine laid down by him in brightness from the brilliant general which seems to me of so much impor- surface to the dark interior, to be more tance that I now propose to discuss it or less gradual. No doubt there are in the fuller light of our recent knowl- many debatable points as to the charedge. I do so all the more gladly from acter and as to the physical interpretathe fact which has recently been im- tion of the spots, on which there is pressed upon me, that even among still a good deal of difference of opinphysicists, and even among those who ion. It fortunately happens, however, have studied the sun with the greatest that for our present purpose the quesattention and the greatest success, tionable points need not concern us. there seems to be no sufficient ac- It is sufficient to note a primary charquaintance with Dr. Stoney's paper. acteristic of a solar spot as to which in Indeed there does not even appear to these days there is not likely to be any be a knowledge of the important phys-dispute. There was a time, no doubt, ical result which he has been the first when it might have been maintained, to establish. I therefore undertake to explain in this article the wonderful part which it seems that the element carbon plays in the construction of the sun, and especially in the discharge of

and, indeed, actually was maintained, that a spot was nothing more than some dark cloud in the upper regions of the solar atmosphere which intercepted the view of the bright surface

lying beneath it and was exhibited to nature is apt sometimes to be lost us as a black object projected against sight of. We, therefore, direct emthat surface. But this view could no phatic attention to the very singular longer be entertained when the spot fact that the internal part of the sun, was followed to the sun's edge, whither of which we are permitted to obtain it was conducted in the ordinary course glimpses through the solar pores or of the solar rotation. If the spot were, through the openings in the interior of indeed, merely an elevated, dark cloud, large spots, is of sooty blackness when then it is quite plain that when it compared with the dazzling splendor reached the solar edge it must totally of the solar clouds. In good solar cease to be visible. The cloud in this photographs the umbra of a spot apcase would stand aloof from the sun, pears absolutely black. I am certainly and could not be perceived for want of not asserting that there is veritable the brilliant background to show it off. darkness in these internal solar reBut it was found that the spots do not gions. Measured by an ordinary standvanish as the edge is approached, they ard, intense light must be present. I are, in fact, often seen quite close up make no doubt that the interior of a to the edge; nay, further, it has some- spot is really far more brilliant than times happened that a large spot is any hall lighted by artificial illuminaactually caught at the very margin of tion on the earth. Indeed, I do not the sun. In such a case the effect pro-doubt that even the blackest part of a duced is that of a notch or "bite "spot has more light than that which our taken out of the bright circular edge. Such an occurrence is a demonstration that the spot cannot be a cloud above the bright solar region, but that it must be an opening through it.

earth receives on the most glorious of summer days. The essential point for us to notice is, that whatever may be the intrinsic brightness of that at which we are looking in the interior of a spot, it is, at all events, dark, quite dark, by contrast with the surpassing glory of the glowing clouds on either side, between which our gaze is directed.

The interpretation of the remarkable granular structure of the solar surface has now become apparent. It is ascertained that the luminosity is due to the bright clouds which float over the solar Various circumstances show us that surface. The clouds are not generally the luminous clouds, encompassing the continuous; there are more usually sun lie in a shell of a thickness comintervening spaces of various magni- paratively slight, when the dimensions tudes. When these intervening spaces of the sun are considered. Take, for are considerable they are called spots, instance, a photograph which shows and in some cases the spots are great the granular structure in perfection. enough for a globe of the size of the To be visible from the distance at earth to be passed through the aperture which we see them, each of these granwithout touching either one side or the ules must have a diameter, let us say, other; at other times, or in other of about a thousand or two thousand places, the spaces between the lumi- miles. Each granule, in fact, reprenous clouds are much smaller, and, sents an area which on this earth indeed, are often suitably described as would be comparable with the territo"pores." In some of Janssen's ex-ries of a mighty kingdom, or even of a quisite photographs obtained after an continent. A cloud of the size of Enexposure of the hundredth part of a second, the porous structure of the sun is beautifully exhibited.

We must now specially refer to the most striking circumstance connected with the constitution of the sun. The study of the spots has made us so familiar with it that its marvellous

gland on the sun would perhaps be only discernible as the minutest point of light. Let us, however, take the case in which the granules have a diameter of a thousand miles each. It is, of course, obvious that we can only see those dimensions of length and breadth which are presented to us; we cannot

directly measure the depth of each sents. We see that the radiation of little cloud. There are, however, many the sun, both as to light and as to heat, scores of thousands of these cloudlets is almost entirely dispensed from the to be seen, and as they all seem much clouds of the photosphere. We see of the same shape we may feel pretty that these clouds are contained in a confident that we are not looking at shell which lies in the outer parts of rod-shaped objects turned endways the sun. We see that the interior of towards us. There cannot be a doubt the sun is comparatively dark, that even that we may safely estimate the depth through the pores, and through the of each granule as a dimension resem- spot openings, it transmits but little bling on the average the length and radiant light and but little radiant heat. the breadth of the objects which are There is, however, no reason to think measured by us. We thus see that the that the internal parts of the sun are solar cloudlets are generally presented less hot than these photospheric clouds as more or less irregularly globular to which we owe so much. Indeed, objects a thousand or more miles in the contrary is, and must be, the case. diameter. We know that a heated body like the The photosphere, which is the term sun must be hotter in the inside than which astronomers apply to the shell it is on the outside. We know that or stratum that contains the luminous from the outside inwards the temperaclouds, is thus seen to consist of float-ture on the whole gradually increases, ing cloudlets of dimensions compara- and thus we learn that the dark inner tively small, when the diameter of the photosphere is considered. We do not say that there is only a single layer of these objects, but it is plain that the total thickness of the stratum must be of insignificant dimensions relatively to the radius of the sun. Dr. Stoney, in his paper to which I am referring, speaks of the photospheric shell as a "film" encompassing the interior of the sun. I do not see that we have any means of determining the thickness of the shell accurately, but to do so is not essential for us. It may be that the photosphere bears the same ratio to the bulk of the sun that the delicate skin of a peach bears to the luscious interior. It may be that the rind of an orange bears a proportion to the fruit inside, which represents the relation of the cloud-bearing stratum to the internal parts of the sun. In this latter case we may imagine that each of the photospheric clouds would be small in comparison with the thickness of the entire shell. In this case, too, the clouds must of course be much more sparsely distributed throughout the extent of the shell, for otherwise they would not permit us to obtain any glimpses whatever of the interior.

regions of the sun, of which we obtain glimpses through the openings in the spots, must be actually hotter than the dazzling clouds of the photosphere. Here, then, we seem almost in the presence of a paradox. It is not from the hottest part of the sun that the heat or the light is chiefly dispensed. If the photosphere were removed it seems that a portion of the sun far hotter than the photosphere would then be fully exposed. It is, however, almost certain that in such a case the light and heat we get from the sun would drop to the tenth part, perhaps to the hundredth part, or even to some smaller fraction of that copious radiation which we now enjoy. It is quite plain that the inhabitants of this earth are indebted, not merely to the fact that there are vast supplies of heat stored in the sun, but to the circumstance that the photosphere is of such a particular constitution that it is enabled to transmit to us some of that wealth of energy, which without the assistance thus rendered the sun would apparently experience much difficulty in getting rid of.

And thus we are brought face to face with the great problem as to what parAnd now we are able to state the ticular element it is whose presence remarkable problem which the sun pre-confers on the photospheric clouds that