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I had turned off the red screen half a minute before and was surprised to behold quite distinctly the following segment of the lunar sphere. The periphery of this segment was more than 100°. Its color was uniformly shaded from an intense black at the centre of the lunar disc to a very dark grayish purple near the limb of the sun. It was still traceable during twenty seconds after the last glimmer of sunlight.
At the moment of totality beads of golden and ruby-colored light flashed almost entirely around the moon not constant even for a second at one point but fitfully flashing as reflection from rippled water, and as mutable in the respective places of the colors. This bead-thread could not have extended more than ten seconds beyond the lunar disc. It broke up suddenly at (1h 16m 21°.2 sid. chron.) and then for the first time protuberances were noted beyond the following limb of the moon. The position of its largest one was 75° or 78° W., and in the form of a flattened cone or pyramid of cumulus cloud about one minute in height and when first observed perhaps two minutes broad at base. The cloud was not a uniform mass but apparently an aggregation of small ones, and its general tint was a rosy pink with occasional spots and edges of yellowish white light as though sunlight shone obliquely through them. Except in the pink color it greatly resembled the protuberance noted during the total eclipse of the sun observed at Olmos, Sept. 7th, 1858. As the moon advanced this protuberance was probably broader at the base and brighter at the summit while its apparent elevation remained the same. This was an extremely beautiful sight, and I watched it closely, giving nearly all my attention to it during 155, yet at the same time I was able to perceive a lesser one of a more flattened appearance distant 10° or 15° towards the west, and several others yet smaller and one long one of a much darker color at different points of the disc. Intently occupied with the great protuberance, the corona had not been recognized up to this instant (Oh 58m 10s), interest in the former causing me also to drop the beat of the chronometer.
It was then so dark that I found it impossible to recognize the second's dial of the chronometer (the gold one) and Mr. James Gilliss was called to bring his lantern and read the time at which I should indicate the second internal contact of the limbs. Raising my face from the box on which the time keeper stood to the telescope a most extraordinary scene was apparent Over the moon's black disc colors of the spectrum flashed in intersecting circles of equal diameter with that body, and each apparently revolving towards the lunar centre. The moving colors were not visible beyond the moon, but a halo of virgin white light encircled it, which was quite uniformly traceable more than a semi-diameter beyond the black outline. This corona was composed of radial beams or streamers, having slightly darker or fainter interstices rather than a disc of regularly diminishing or suffusing light'; but the gorgeous appearance of the spectrum circles with their incessantly changing bands of crimson, violet, yellow, and green, thoroughly startled me from the equanimity with which the preceding phenomena had been observed. Nor were these colors physiological results from a change of position of the body, or of preceding strain of sight in efforts to recognize the division of the second's dial, in darkness, and subsequent direction of the eye towards the
sunlight, for they continued visible with the telescope at least 10° longer. As near as it was posible to estimate, the breadth of each spectrum circle was about two minutes. The green colors were not darker than the tint usually called pea green, and were on the edges farthest from their respective centres, but neither of the lines seemed to retain a definite position, and I was irresistibly drawn to their contemplation to the neglect of all the changes that might have been taking place in the protuberance and corona. They vanished with the first appearance of sunlight beyond the western limb of the moon, their sudden obliteration causing me to utter an exclamation which was regarded as the signal for noting the time, a datum whose importance had been wholly forgotten in the fascination thus caused. I cannot liken them to anything so nearly as to the image seen in the kaleidoscope.” 3. Observations made during the Total Eclipse of 18th July, 1860, on the summit of Mount Saint-Michel, in the Desert of Palmas, Spain; by A. SEccHI, S.J. Communicated to the French Academy of Sciences. (Comptes Rend., li, p. 156, July 30, 1860.)—The place where I observed the eclipse was on the top of Mount Saint-Michel, in the desert of Palmas, at the same point chosen by Biot and Arago for their triangulation operations, and at a height of 725 metres (=2378 ft.) above the sea, commanding a very wide horizon. The weather was magnificent during the whole time of obscuration, notwithstanding we were tormented with a cruel anxiety up to a few moments of the time by parasitic clouds forming continually on the mountain and dissolving only when at some distance. But they happily disappeared just before the critical moment, and the sky was fine till evening. I was accompanied by M. de Aguilar, director of the Madrid Observatory, and by Mr. Cepeda, lawyer from Valencia, a distinguished amateur. The instruments were a Fraunhöfer telescope of 78 mm. aperture (about 3:04 inches) and 1m 20 (=474 in.) focal length, with powers of 60, 90, and 130 diameters. The two first powers gave the entire disc of the sun, and the three oculars being mounted on a slide could be changed with the greatest rapidity. The micrometer carried a system of six spider lines, with spaces of 6' (invisible in the dark), and of four very fine platinum wires so disposed that there was a space just equal to one lunar diameter between the outer wires—the two intermediate wires were slightly inclined, subtending 1' 30" at the narrower, and 2' 30" at the larger angle; an arrangement designed to aid in obtaining a more exact estimate of the protuberances. The whole micrometer revolved on a transom, with a plate on which was a graduated circle and a sheet of white drawing paper upon which the angular position was marked by touching a pencil, carried by the fixed transom—thus reserving the reading until the observations were concluded. This instrument was mounted equatorially, was very stable, and had been adjusted the day before.
* Up to this date, Sept. 7th, the party sent to the Cumberland House, British Columbia, have not been heard from.—EDs.
Some minutes before the commencement of observations I verified the position of the telescope and the commencement was marked by a Morse telegraph, kindly procured from Madrid by M. Aguilar, provided with a pendulum which marked the seconds. A simple mechanism marked the instant of observation. Some minutes after the commencement I sought for the disc of the moon outside of the sun but could not make it out. At 2h 19m I succeeded in seeing very clearly through an arc of about 10° or more, but some time after the moon disappeared, and after that it could be observed only for an instant. Is this due to the inequality of the portions of the solar corona, upon which the disc of the moon is projected ? I observed with certainty that not only the edge of the solar crescent was more sharply defined upon the side of the concave phase, than upon its own proper border, but also that the field of the telescope was much more clear upon this side than upon that of the moon, and the same could be seen in projecting the solar image on white paper.
The cusps remained throughout very distinct, and the solar spots were successively eclipsed without any distortion as viewed with a magnifying power of 90. The lunar mountains were well outlined upon the solar ground, and indented the inner border of the limb. After the centre of the sun was hidden (and even a little more) the light of the horizon diminished suddenly in a decided and unexpected manner. Surrounding objects did not however noticably change color. As the eclipse was becoming nearly total, I took away all the fixed colored glasses, and followed the sun with a glass held in the hand. This was an excellent glass of neutral tint made by Lerebours, a graduated light, the lighter shade being very delicate. The slender crescent is now breaking into many parts near the cusps which still remain very distinct, and the corona begins to show itself even with the dark glass. The sun reduced to a simple thread disappeared without forming (grains des chapelet) Baily's Beads. Quickly taking away the colored glass I was surprised to see the sun yet white and its light so strong that it hurt my eyes, but its splendor visibly diminishing and changing to a purple light, which at once appeared to terminate in an infinity of purple points, which were as soon hidden, and then two great red protuberances appeared near the point of occultation. One of these was at least 2' 30" in height, and as large at the base as 2'; it was conical in form, slight! tapering, curved at the top. The other was about half the height of the preceding, extending over a considerable are, at least 5° upon the solar border. Its top was formed like very minute saw teeth, parallel to the border of the moon. I looked as soon as possible at the opposed margin of the sun, but nothing appeared. . Returning to the first margin I saw that the protuberances were rapidly hid. During the whole time the corona was magnificent but most brilliant on the side on which the eclipse began. Its light was all around uniform and without interruption, of a beautiful silver white, shading off gradually from the margin of the moon to the distance of about the lunar radius or less. At this distance there began to be many interruptions; large sheafs of light appeared, those of the upper part were the largest, and extended out to a distance equal to a diameter and a quarter of the moon. On
AM. JOUR. SCI.-SECOND SERIES, Vol. XXX, No. 89.—SEPT., 1860.
the lower part I saw only one of these long sheafs. With Arago's polariscope, already directed very near the sun, I ascertained that the two images were not of equal brilliancy, and that the corona in one was lengthened in one direction, and in the other in a direction perpendicular to the first, but I could only give some seconds to their examination. Returning to the telescope, I regarded for an instant the imposing scene which was then displayed in all its majesty. The moon perfectly black showed itself with all the glory of its rays, which appeared lengthened below and to extend out to the distance of two solar diameters. The heavens were of a light ash color, but not of threatening aspect. Near objects were plunged into feeble twilight contrasting with distant objects not yet in shadow. All this unique scene remains profoundly engraven on my mind; the solemnity of the spectacle appeared forcibly to impress the assistants, who, though numerous, all remained in perfect silence. Not to lose these precious moments I returned immediately to the telescope. The aspect of the sun was much changed. The two great protuberances of which I have spoken had already disappeared, and a great number of others appeared from on all sides of the sun (this moment corresponding to the middle of the total obscuration), I was for an instant embarrassed to decide which to select for measurement of their angle of position; for it was useless to measure the size, which changed while looking at it. With the mechanism of the micrometer in a few seconds I determined six—although I counted at least ten—there was hardly any part of the surface of the disc where there was not a point, they seemed regularly distributed. These are the angles taken in reckoning from east to northwest. South: 39-0°, 75:0°, 116:0°, 173:0°, 211:39, 310.0°. A greater brilliancy of the corona on one side announced that the sun was emerging, then in directing my attention to this side I was astonished to see a very large number of very small protuberances, and above all of them a red cloud entirely detached which was suspended and separate from the rest and from the lunar margin by a marked white space. Its figure was elongated, about 30” of length to 3" of width, and its form somewhat tortuous and sharp at the extremities (I called to my companions to witness this). This cloud was not alone. I had the conviction that it was accompanied with many others which rested at nearly the same level as a series of cirrus. Their color was that of the protuberances, only a little more distinct. During all this the number of protuberances increased greatly upon this side and soon assumed a continuous arc formed like a saw, which extended at least to 60° of the circumference, and which gradually lengthened while its central part increased in width and brilliancy. The purple color mingled with the white in gradual transition until the white became so strong that the eye could not sustain it; the protuberances then disappeared. The sun then began to shine in the heavens like a point of true electric light, and made a singular contrast with the corona still remaining, and which (by hiding with my hand the bright part) I could see for 40 seconds longer. That which most struck me in the circumstances, was the immense quantity of red protuberances and their distribution; so that one could absolutely say they enveloped the sun. Those commonly observed are only the summit of the most elevated, and without doubt it is only in certain favorable circumstances that we can see the sun entirely crowned by them. This corona of light prevented accurate observations of time, and it would give a different solar diameter according to the depth of shade of glass employed. The time of total obscuration was found by M. Cayetano de Aguilar to be 8m 11°, but it passed like a moment and seemed to us, at the most, not more than two minutes. My convictions upon the nature of that which I saw are that the phenomena were real and that I truly saw the flames in the solar atmosphere and clouds suspended in these flames; it would be impossible to imagine anything else, as for example, that it might be some phenomena of diffraction or refraction. The clear graduation and distinct mingling of the peach blossom colored light with the white photosphere was of a character so distinct that it can never be mistaken by any phenomena of interference, of refraction, or any illusion whatever. I do not doubt that it really appertains to the sun, and the structure of these suspended clouds tends to strengthen my conviction. As regards the part of the corona more remote and those long bundles of rays, the thing does not appear to me so certain: they have too much the aspect of those seen through the clouds at sunset. Yet it is important to distinguish from these the true corona which was continued much beyond the protuberances. M. Cepeda, however, who made his observations with an excellent telescope, having a large field, assures me that he saw a bundle of rays, curved and branched like the horns of a stag, at the upper part. All these observations have been confirmed by photography. The director, M. Antonio de Aguilar, had brought, for making the solar photographs, the large telescope of Cauchoix, mounted upon a solid cast iron foot, furnished with clock-work. Besides numerous proofs of the entire sun, he took 14 impressions on a larger scale, and 5 of the natural size of the focal image, 23 millimeters in diameter, and which represent all the phases of the phenomena. The examination of these photographs will be made under more favorable circumstances with proper instruments. At present, I will only say that the times of exposure varied from from 35 to 30°, that all the images are solarized in the protuberances, but the corona has an intensity differing according to the time. There was not the same intensity throughout but the most vivid parts do not correspond to the protuberances. We notice also a greater intensity in the chain of protuberances toward the first and the last instant of total occultation. The force of the light of the protuberances is such that one impression is become triple by a momentary jar of the telescope. In this delicate operation M. Monserat, Professor of Chemistry in the University of Valentia, was charged with all photographic operations, and my compeer, P. Vinader, took charge of the regulation of the telescope. This communication has already become so long that I omit ordinary observations, and will only say that the light was strong enough to enable one to distinguish small objects, and to read without difficulty ordinary books; and without