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ing-stick," while he ought to have been es- bring out a book of which passion occupies pecially merciful, seeing that the book was so great a portion. This chapter is unnewritten soon after he had lost much money cessary; strike it out.' So the frightened in speculation. His wife's humorous com- author suppressed this chapter also. Once plaint runs as follows:
upon a time, too, in these pages were two "Once upon a time there might have morsels of verse. The one was a satire, the been found in this romance
other an elegy. But somebody decreed “But it is not a romance."
that the satire was too pungent, and the “In this work
elegy too melancholy. So the author gave “But it is not a work."
them up, but this conviction she keeps, “ In this book
That a woman who sees the world ought “Still less should it bear the title of a to refrain from writing, since she may bring book.”
to the light nothing but what is perfectly “ In these pages, in fine, once upon a insignificant.” time, there was a somewhat piquant chap- Poor Delphine Gay! We know not ter entitled “The Council of Ministers.' whether “ to love, honor, and obey," formBut somebody said to the author, 'Be ed one of the promises of her marriage careful, this is personality—these person- ceremony; the fulfilling it, however, seems ages will be recognized : do not publish to have been somewhat hard for her. Yet, the chapter.' And the obedient author when her ungrateful husband was in prison canceled the chapter accordingly. There on account of his political views, she unwas another chapter, entitled A dream of derwent all sorts of dangers for him. This Love.' It was a rather tender love-scene, sentimental poetess and lively novelist as a picture of passion ought to be in a was certainly not a bad specimen of a woromance. But somebody said to the au- man. thor, “It is not proper on your part to
[From London Society.
THE LATE SOLAR ECLIPSE.
BY RICHARD A. PROCTOR, B.A., F.R.A.S.
ASTRONOMERS have seldom reaped a million degrees centigrade, or some eighmore abundant harvest of facts during a teen million degrees of the common thertotal eclipse (making hay, after their fash- mometer, (in which 180 degrees above ion, when the sun is not shining) than they freezing represents the heat of boiling wadid during the eclipse of December 12th ter.) On the other hand, we have a theolast. To say that the anticipations which ry maintained by Faye, St. Claire Deville, they had formed were amply fulfilled, Fizeau, and many others, according to would be to say far less than the truth. which the sun's heat does not greatly exAlthough all hoped that important facts ceed that obtained in the electric light, and would be discovered, few expected so com- is certainly comparable with the heat obplete a success as has actually been tained in many processes of manufacture. achieved. Then, for the first time, the Indeed, according to some of the most wonderful complexity and magnificence of satisfactory investigations which this subthe solar surroundings were clearly reveal- ject has received, the actual heat at the ed.
sun's surface does not very greatly exceed Of the actual nature of that intensely that at which iron melts; while St. Claire hot and brilliant surface which the sun pre- Deville even asserts his belief that a degree sents to our study, we can say but little. of heat not greatly beyond that which our Astronomers are not certain even whether physicists have obtained can not possibly it is liquid or gaseous, and at present their be exceeded under any circumstances, eithideas respecting the intensity of its heat er in our own sun or in any of his fellow are in most unsatisfactory disagreement. suns. On the one hand, we have a theory by
Above the glowing photosphere, or light Father Secchi, the eminent Italian astrono- surface of the sun, there extends to a depth mer, according to which the heat of the of several hundred miles the most wondersun's surface is certainly not less than ten ful atmospheric envelope known to astronoIn dealing with this envelope, we ined alone, could show bright lines preare touching on the work of the recent cisely where the solar dark lines appear,eclipse, because, although the envelope sufficed exactly to fill up the gaps caused had been recognized theoretically two years by the absorptive action of those vapors, ago, and its existence demonstrated during Secchi reasoned in this way: If we exthe eclipse of December, 1870, yet doubts amine the intensely bright light of the sun had continued to be entertained by a few shining through these vapors, we see that respecting the reality of this relatively shal- this light is deprived of certain rays, and low atmosphere. We can now, however, so dark lines appear; but if we could ex. speak of it unquestioningly, since scarcely amine the light of the vapors themselves one of those who sought for it during the we should see that this light is composlate eclipse failed to recognize its existence. ed of these selfsame rays, and so bright
In the lower part of our own air there is lines on a dark background would appear. always present, in greater or less quanti- Now the latter we can not do on account ties, the vapor of water. This vapor rises of the extreme shallowness of the complex from wet earth, from rivers, lakes, and seas, atmosphere; we can, however, by examinand from the wide expanse of ocean, and ing the very edge of the sun, obtain light occupies a certain portion of the lower at- so combining the two kinds, that there will mospheric strata. Thus these lower strata neither be dark lines on a bright backform as it were a more complex atmosphere ground nor bright lines on a dark backthan those above them. Close by the ground, but a continuous rainbow-tinted earth there is air and aqueous vapor, while streak produced by combination of the in the higher regions there is air alone ;* two. that air being, as we know, composed of It seemed to Professor Young, of Ameria certain admixture of the two gases, oxy- ca, that during eclipses something more gen and nitrogen. Now in the case of the might be achieved. For at the very mosun, a somewhat similar arrangement ex- ment when the moon has just concealed ists. The lower regions of the solar at- the true solar disk, the light of the shallow mosphere are at all times occupied by cer- atmosphere must be shining alone. Dutain vapors, which ordinarily do not rangering the eclipse of December, 1870, he had to any considerable elevation, simply be- his telescope directed (and kept directed cause they can not remain in the form of by clock-work) toward the point where vapor except close by the sun. But these the moon would obliterate the last fine vapors are such as we should be rather edge of direct sunlight. And he prepared startled to find in our own atmosphere. an ordinary telescope for the use of Mr. We breathe the vapor of water without in- Pye, (a young English gentleman residing convenience, unless it is present in too near the place where Professor Young's great quantities; but if we could imagine party were stationed,) and instructed Mr. for a moment that there were breathing Pye what to look "for. Both observers creatures on the sun, these must be able to found that as the rainbow-tinted streak inhale without injury the vapor of iron, forming the solar spectrum faded away at copper, zinc, and others of our familiar the instant of totality, there sprang into metallic elements. For the solar atmos- 'view a myriad-lined spectrum—the specphere, to a depth of a few hundred miles, trum, in fact, of the sun's true atmosphere is loaded with these vapors, all glowing now for the first time recognized. with intensity of heat.
During the recent eclipse, Colonel TenNow Father Secchi announced in 1869 nant, Captain Maclean, and several other that he had detected traces of just such an observers, saw the beautiful bright line atmosphere. For when he examined with spectrum of the sun's glowing atmosphere. his spectroscope the very border of the One or two observers failed to do so; but sun, he found that the dark lines could no it need hardly be said that these failures longer be seen; as though the light of the prove nothing except the extreme delicacy glowing vapors themselves,—which exam- of the observation. The positive results,
which need alone be considered, prove de* Here we are considering only the main con- cisively that next above the sun's light surstituents of the atmosphere. Relatively minute face there lies an exceedingly complex, but the upper as well as in the lower regions of the relatively shallow, atmosphere, loaded with air.
the glowing vapors of all those elements metallic or otherwise to which the dark insomuch that some astronomers expressed lines of the solar spectrum are known to their belief that this envelope is a perpetube due.
al solar aurora. The startling nature of Next in order comes the sierra, or red this conception will be realized when it is envelope, sometimes called the chromo- mentioned that at a moderate computasphere, (or more correctly the chromato- tion the ring-formed corona has a depth sphere.*)
exceeding twenty times the diameter of the The sierra is a far more extensive atmos- earth on which we live, while the actual pheric region than the complex atmos- portion of space occupied by these auroral phere of Young and Secchi. Its average lights (if the theory be true) must exceed depth is probably about five thousand the volume of the earth more than fifty miles. Its chief constituent is glowing thousand times. Besides such displays as hydrogen, but it contains other elements, these, the most glorious auroras that have and is indeed far less simple in constitu- ever illuminated terrestrial skies sink into tion than was supposed a year or two since. utter nothingness. That this is so, is proved by the fact that But some difficulty was experienced in Professor Young has counted one hundred demonstrating that the spectrum on which and twenty lines in the spectrum of this these ideas had been based belonged in red atmosphere.
reality to the ring-formed corona. The Above the red sierra, and reaching even study of the sun's surroundings by specbeyond the loftiest prominences, lies yet troscopic analysis is not free from certain another atmospheric envelope, the inner causes of perplexity. To show how these corona, as it has been called.
may arise, we need only consider a case The consideration of this important solar whích any one possessing a small spectroenvelope leads us to one of the most im- scope (one of Browning's miniature specportant of the discoveries made during the troscopes, for instance,)
can readily test for late eclipse. It had long been recognized himself. If such a spectroscope be turned that the solar corona appears to consist of (with suitable precautions) towards the two portions distinct from each other. sun, we see the principal solar dark lines, The inner portion received (from the As- and we know that those lines teach how tronomer-Royal
, we believe,) the name of the sun's light is partially absorbed by the the ring-formed corona, because not mark- vapors of certain elements existing in his ed by any noteworthy indentations, gaps, atmosphere. But if next we direct the inrifts, or the like, but presenting the appear- strument towards the sky, we see precisely ance of a somewhat uniform ring of whitish the same spectrum, only reduced in splenlight around the black disk of the eclipsing dor. Yet the vapors of iron, copper, zinc, moon. It was to this corona that some of and so on, do not exist in the sky. The the observers of the eclipse of December, fact really is, that we receive from the sky 1870, mistakenly supposing its recognition reflected sunlight, and therefore we can at that time to be a real discovery, propos- trace in the spectrum of skylight the dark ed to assign the name leucosphere. The lines belonging to sunlight. And in exterm was intended to indicate the apparent actly the same way, the sky during total whiteness of the inner corona. But under eclipse, though not very brilliantly illumifavorable circumstances the envelope pre- nated, is nevertheless lit up to some extent sents a slightly ruddy tinge, with traces of by the corona, prominences, and chromagreen.
tosphere, and therefore the sky-light must Astronomers had begun to recognize the supply, however faintly, those bright lines fact that the inner ring-formed corona must which belong to the spectrum of the gasebe a solar appendage, whatever may be ous solar surroundings. How is the obthought of the fainter radiated corona server to tell, when he obtains these bright which surrounds it. The light of the ring- lines from any given part of the corona, formed corona had been examined with that they actually belong to that part of the spectroscope, and appears to resemble the corona and not to the light of the sky ? in some respects that of the aurora borealis, Now Professor Young, in December,
1870, dealt with this difficulty in a very * Strictly speaking, the word chromosphere is subtle and masterly manner. There are graphy, chromic for chromatic, or (vice versa) two different ways in which spectroscopic chronatic for chronic.
analysis can be applied. In one we are analyzing the light from a considerable siders. But suppose he uses no slit, then range of space, in the other we study only instead of a series of images of a slit he that light which comes from a certain defi- will have a series of images of the source nite direction. Professor Young, who had of light. If the source of light is the sun applied both methods to the shallow com- or any object shining with all the colors, plex atmosphere, applied both, with similar the different images will overlap and he success, to the inner corona. Let us sup- will see simply “ Newton's spectrum," a pose that by the former method the whole rainbow-tinted streak of extreme beauty of the region of sky occupied by the inner and splendor, but nevertheless what the corona was supplying light for the spectro- spectrocopist describes as an “impure scope to analyze; and that by the latter spectrum,” because in it a multitude of only a fine linear strip from the brighter overlapping images are present. If, howpart of the inner corona was being analyz- ever, the source of light emits rays of cered. Then clearly and without entering tain colors only, then there will be separate into niceties of detail, if the bright line images of these colors, each clearly disspectrum we are considering belongs in cernible in all its details. For example, reality to the inner corona, we should let us suppose that in a little conical flame find the true coronal lines relatively much of great heating power but small luminosbrighter by the former method than by the ity, a chemist places a small quantity of latter. For in the former there is the great sodium and lithium. Then when he looks extent of the inner corona to compensate at the flame through a spectroscope withthe feebleness of its inherent luminosity, in out using a slit he will see a little conical the latter there is no such compensation. yellow flame, and close by it a little coni
Carefully studying the relative bright- cal and rather faint orange flame, and farness of the suspected coronal lines, when ther away a little conical red flame; wherethe two methods of observation were ap- as if he had had a fine slit in his spectroplied, Young inferred that a certain green scope he would have seen three fine lines, line belongs unquestionably to a region of a yellow one due to the sodium, and two luminous matter not less extensive than the lines, one orange and the other red, due inner corona. It appeared tolerably safe to the lithium. to conclude that the inner corona was the Now if the reader has followed this actual source of this peculiar light. And brief but necessary explanation, he will see if the resemblance between this light and that the astronomer possesses the means that of the aurora borealis were admitted, of at once solving the difficulty of the coit appeared reasonable to infer that the in- rona. So long as he used a slit he obner corona is a perpetual solar aurora, as tained a bright green line which might not had been suggested in 1869.
come from the corona, but from the illuBut although the reasoning of Professor minated sky in the same direction; but if Young was so conclusive that he must be he removed the slit and then saw a green regarded as in effect the discoverer of the image of the corona, he would no longer important facts just mentioned, yet it seem- be in doubt. For the illumination of the ed desirable to astronomers to endeavor to sky could not form an image of the corona, obtain even more convincing evidence. any more than the sky we see in the dayThey had hitherto dealt with the spectral time forms images of the sun, though shinline or lines of the inner corona. Those ing with solar light. If the observer exlines are in reality colored images of the amining the corona with a suitable specslit through which the spectroscopist ad- troscope not provided with a slit saw a mits the light which he proposes to exam- green image of the corona, it could only ine; and therefore their shape can teach be because the green light came from him nothing about the source of light, their those parts of the sky where the corona position (or which is the same thing,* their was actually seen, and from no other parts. color,) being all that the spectroscopist con- Now this experiment was precisely what
Respighi, the eminent Italian astronomer, * Because a bright line corresponding to any determined to attempt. He had an inposition along the rainbow-tinted spectrum has strument (made for him in 1868) which the color proper to that position. Spectroscopists seemed to him admirably adapted for the indicate the position of a line by reference to color -saying a line in the red, or in the blue green, or
purpose; and accordingly he took this inthe like.
strument with him to India; and stationed at Poodocottah, he successfully applied it hydrogen, another in the green,” (correto the solution of the problem which had sponding with Professor Young's green so long perplexed astronomers. His ob- line,) “and a third in the blue, probably servations involved results of interest, re- corresponding with the blue line of hydrolating to the colored prominences, since gen.” these as well as the inner corona were pre- Thus not only has the fact been proved sented in spectrally shifted images. that the light producing the green lines
“At the very instant of totality,” he comes, as Young had reasoned, from the says, “ the field of the telescope exhibited inner corona, but also that this corona a most astonishing spectacle. The chroma- consists in part of glowing hydrogen. tosphere at the edge which was the last to And when we say " in part," we do not be eclipsed, surmounted by two groups of mean that throughout a portion of its exprominences, one on the right, the other tent the corona consists of hydrogen ; but on the left of the point of contact, was re- that one of the elements of which the coroproduced in four spectral colors, with ex- na is formed is the familiar gas hydrogen. traordinary intensity of light, and the most It appears from the sequent remarks of surprising contrast of the brightest colors, Professor Respighi that the hydrogen exso that the four spectral images could be tends as far, or very nearly so, as the matdirectly compared and their minutest dif- ter, whatever it may be, which produces ferences easily made out. All these images the green light of the corona. Before were well defined, and projected in certain quoting his words, we remind our readers colored zones, with the tints of the chro- that what Respighi saw was three pictures matic images of the corona. My atten- of the corona in three different places— tion was mainly directed to the forms of one picture produced by the red part of the prominences, and I was able to deter- the corona's inherent luminosity, another mine that the fundamental form, the skel- by the green part, and another by the eton or trunk, and the principal branches, blue part of that luminosity. The three were faithfully reproduced or indicated in zones he speaks of are not three distinct all the images, their extent being, however, envelopes, but three pictures of one and greatest in the red, and diminishing succes- the same element. Just as the spectrosively in the other colors down to the in- scopist in the case of our imaginary experidigo images, in which the trunk alone was ment with the lamp-flame could not infer reproduced. In none of the prominences that there were three small conical flames, thus compared was I able to distinguish because he saw three images of the single in the yellow image parts or branches not small conical flame, so Respighi knew that contained in the red image.* Meanwhile the three rings of light which his telescope the colored images of the corona became (spectroscopically armed) presented to his continually more strongly marked, one in view, were spectral images of one and the the red corresponding with the red line of same object, the inner ring-formed solar
corona. * The interest of the question whether such
“ The green zone surrounding the disk differences would be perceived resides in the fact of the moon," he says, “ was the brightest, that the red, green, and indigo images are all due the most uniform, and the best defined. to hydrogen, but the yellow to another element, The red zone was also very distinct and to ascertain whether this element extended be well defined; while the blue zone was yond or not so far as the hydrogen. For our own faint and very indistinct. The green zone part we are disposed to place very little reliance was well defined at the summit, though on some of the facts observed in this particular less bright than at the base; its form was low images shining in full splendor he would na- sensibly circular and it sheight about six turally be unable to see the fainter parts of the in- or seven minutes,” (corresponding to a real digo images ; but these darker images are proba- depth of from 160,000 to 185,000 miles.) bly at least as extensive as they are certainly as “The red zone exhibited the same form, well defined as the others. For Secchi, in study and approximately the same height as selects the indigo images for the purpose, because the green ; but its light was weaker and he has found that cæteris paribus the indigo images less uniform. These zones shone out upon other things were not equal. Similar remarks a faintly illuminated ground without any apply to the apparently inferior extension of the marked trace of color. If the corona conblue green image of the inner corona.
tained rays of any other kind, their inten