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admiration at the glorious spectacle of the corona, and, the prominences of rose-colored flame, which surrounded the moon. The appearance of the corona is not so well described by calling it a ring, or halo of light, as by comparing it to the 'glory' or ' aureola,' employed by painters to designate the person of the Saviour.” It seemed to extend from the moon's edge over a space about equal to that of the sun's semi-diameter, though its external outlines were rather indefinite. Its light was pure white.
Professor Bond was absolutely certain that the corona was visible on the moon's limb after the sun's limb had reappeared. He saw several prominences, some on the side of the moon's advance, and others on the opposite side. "The color of all was a decided rose, or pinkish-carmine ; like the roseate hue of auroral streamers, but far more intense. He says that all the prominences" had rather the appearance of flames, not in sudden motion, than of mountains, or of solid projections from the sun, to which they seemed to belong rather than to the moon.
Mr. John Russell Hind has given us a very beautiful description of terrestrial phenomena, as they appeared during the period of totality, which lasted only 1' 40" near Engelholm, in Sweden, where he observed. We quote it here :t
“ The aspect of nature during the total eclipse was grand beyond description. A diminution over the earth was perceptible a quarter of an hour after the beginning of the eclipse, and about ten minutes before the extinction of the sun the gloom increased very perceptibly. The distant hills looked dull and misty, and the sea assumed a dusky appearance, like that which it presents during rain. The daylight that remained had a yellowish tinge, and the azure blue of the sky deepened to a purplish-violet hue, particularly towards the north. But, notwithstanding those gradual changes, the observer could hardly be prepared for the wonderful spectacle that presented itself when he withdrew his eye from the telescope, after the totality had come on, to gaze around him for a few seconds. The southern heavens were then of a uniform purple-gray color, the only indication of the sun's position being the luminous corona, the light of which contrasted strikingly with that of the surrounding sky. In the zenith, and north of it, the heavens were
* Astron. Jour., vol. ij., p. 50.
of a purplish-violet, and appeared very near, while in the northwest and the northeast broad bands of yellowish-crimson light, intensely bright, produced an effect which no person who witnessed it can ever forget. The crimson appeared to run over large portions of the sky in these directions, irrespective of the clouds. At higher altitudes the predominant color was purple. All nature seemed to be overshadowed by an unnatural gloom; the distant hills were hardly visible; the sea turned lurid red, and persons standing near the observer had a pale, livid look, calculated to produce the most painful sensations. The darkness, if it can be so termed, had no resemblance to that of night.”
The predicted and observed boundaries of the shadow in this eclipse accorded very closely. Dr. B. A. Gould (Sen.) says that "the vessels passing through the sound by Elsinore saw the Swedish coast on the outside in the gloom of deep shadow, while Denmark, opposite, was glowing in bright sunlight.”*
On the 7th of September, 1858, there occurred a total eclipse of the sun, in which the whole shadow of the moon passed obliquely across South America, a few degrees south of the equator. The late Captain J. M. Gilliss went to Olmos, in Peru, a small town in the outer range of the Andes, where he observed the eclipse nearly in the centre line of the totality. The whole period of totality there was but sixty and a half seconds. The eclipse took place in the morning, the middle of the eclipse being about half-past seven, and the prospect was at first unfavorable, owing to the presence of clouds, which prevented the beginning of the eclipse from being observed.
Before the beginning of totality, by twelve or fifteen seconds, the entire lune, then perhaps 35° in extent, broke up into masses of unequal length, showing detached portions wholly separated from the rest by dark lines. The suddenness of the occurrence was such as to startle him. Within the following ten seconds the remaining visible fragments had become brilliant globules, of nearly equal size, but they differed from Baily's beads, as seen by him during the annular eclipse of September, 1838, by the darker spaces which'separated them from one another.
* Astron. Jour., vol. ii., p. 51
When the total obscuration commenced, four luminous clouds immediately became visible on different parts of the moon's circumference. Circumstances did not permit him to decide which one was first recognised. All the phenomena were distinctly visible with the naked eye, as he perceived while removing the screen from the telescope. One of the clouds, or protuberances, was thirty seconds of arc in height, and occupied more than 30% of the lunar circumference. The highest of them was as much as minute, or one minute and ten seconds, in altitude, above the margin of the lunar disk. A marked peculiarity of these clouds, as seen from that station, was the absence of rose or pink color,“ but they all resembled irregular masses of illuminated clouds of leaden hue, fringed with bright light, more especially at the edges furthest from the sun.” Lieut. Gilliss was surprised at the absence of any red color, and thinking that his physical condition might have some influence, he requested Mr. Raymond, his assistant, to carefully note the color of the protuberances, and he says that they appeared to be of nearly “the same color as the corona, making it look more intensely bright. There was no pink or red colour exhibited.” At Payta, however, the French observers saw them “of a bright rose color.”
The corona of light flashed out at the moment of totality. He says that it extended farthest from the sun, in lines drawn from the centre, through the protuberances, but it did not extend any where beyond 15° or 16° from the margin of the lunar disk. “It was a far more imposing sight,” says Lieut. Gilliss, “ without, than with the telescope, and long as has been my experience in the observation of celestial phenomena, and calm and unimpassioned, at such times, as my temperament has become, the sublime majesty of the scene thrilled me with excitement and humble reverence.” It had a similar influence on two citizens of Clinos, who stood within a few feet of him, watching with deep interest the gradual decrease of light. At the instant of total obscuration one of them exclaimed in terror, “ La Gloria !” and both fell to their knees, "filled with awe.” The darkness of totality was not
great, for Lieut. Gilliss made all his sketches without the aid of artificial light.*
On the 18th of July, 1860, there occurred a total eclipse of the sun, which was rather remarkable for the extent of the earth's surface throughout which it was visible. The sun rose eclipsed in the western part of the United States, and the zone of totality passed over British America, traversed Spain from north to south, passed thence into Algiers, and disappeared in the interior of Africa. Astronomers in America, and in most parts of Europe, placed themselves in the path of the moon's total shadow, for the purpose of observing so sublime a phenomenon, and from which they expected to derive much important information in relation to the physical constitution of our great central luminary.
In this country two expeditions were fitted out, one by the United States government and the Coast Survey, conjointly, which proceeded to Labrador, on the east coast of North America ; and the other by the Coast Survey, and sent to Washington Territory, in the west part of the United States. The first party, under the direction of Professor Alexander, of the College of New Jersey, were prevented by unfavorable weather from making satisfactory observations on the eclipse.+
The other expedition, in charge of Lieut. Gilliss, went to a station near Steilacoom, and was more fortuuate. The remarkable character of Lieut. Gilliss' observations, renders a somewhat detailed account of them necessary. The sun rose eclipsed about half-past four in the morning. After totality had begun he could see the following segment of the moon through an arc of 100° or more. “Its color was uniformly shaded, from an intense black at the centre, to a darkgrayish purple on the western border, and for the first time in my life,” says Lieut. Gilliss, “ the moon was visible in its true form--a sphere, and not a disc.”+
At the moment of totality, beads of golden and ruby
* Smithsonian Contributions to Knowledge, vol. vi., Total Eclipse of the Sun, Sept. 7, 1858, pp. 7-11.
+ Coast Survey Report for 1860, pp. 229_275.
Coast Survey Report for 1860, p. 285.
colored light flashed almost entirely around the moon. These were continually changing in dimensions and color. This band was about 10" or 12" in width. It was generally separated from the dark margin of the lunar disk by a delicate line of white light, which disappeared as the changes of form or color took place. It lasted about twenty-seven seconds, after which, for the first time, he saw protuberances. These last did not differ from similar phenomena seen during former eclipses, sufficiently to call for a particular description. Of one of them, he says that he was “positive that it was uncovered by, and did not cover the moon.” After giving special attention to one protuberance, he further adds -- and this is of great importance, coming from so accurate and reliable an observer as Lieut. Gilliss—that “this examination confirms an opinion formed in 1858, and I am most thoroughly convinced that the masses which became visible, apparantly around the lunar disk, were really clouds belonging to the solar atmosphere."*
His attention was so thoroughly fixed on the principal solar cloud, that he lost the beat of the chronometer, and it became necessary to look at the dial of the instrument. In so doing, he took a hurried look at things between the northeast and south-southeast. “But it was as dark as night," and he could only see a shadowy outline of the near forest. He was away from the telescope not more than eight or ten seconds; but when he again looked at the sun, he found that a totally different picture had been substituted for the black disk before seen enriched with "a tremulous band of vermilion, or red, or yellow lights, overlapped by the solar clouds." The disk, as now seen, was thrown in bold relief upon a ground of pure white, treaceable in all directions for the distance of a semi-diameter. The solar clouds were still visible, but the gorgeous circlet, before mentioned, was gone, and over the black surface of the moon, colors of the spectrum apparantly flashed in circular bands of equal diameter with the lunar disk. Each band seemed to be about two minutes of arc broad. Its colors were crimson, or red, violet, yellow,
• Ibid, p. 286.