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Read Ebook: The proceedings of the Canadian Eclipse Party 1869 by Ashe E D Edward David
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Let B F be the height of the protuberance, and L B the line of sight, tangent to the point B, and let the lines of sight, both direct and reflected, be considered parallel to each other; now, through the point D draw a tangent, and let the incident ray, F D, and the reflected ray, O D, make equal angles with it; then, the exterior angle, O D C, is equal to the angles D AC and A C D; take away the right angles, D and A, and we have the remaining angles, O D E and C, equal; and B A is equal to the versine of the angle of reflection.
But the fault of the Canadian party consists in not having photograms similar to those of the American astronomers, which all more or less agree with each other. This is extremely hard, and although I congratulate those gentlemen on their well earned reputation, still I trust that our photograms, instead of contradicting one another, will be found consistent.
I believe that Jefferson City was the most westerly place where photograms of the eclipse were taken, and directly totality finished with us, it commenced at Des Moines, so that the photograms taken there must be compared with ours.
In conclusion, I congratulate those gentlemen who so kindly assisted me on our complete success, especially my dear friend and old ship-mate, Professor Stephen Alexander, without whose assistance no Canadian party would have been formed; and also, Mr. Vail, of Philadelphia, who kindly joined our party, and whose annexed report gives such ample proof of the value of our negatives.
E. D. ASHE, Commander, Royal Navy, Director Observatory, Quebec.
June 22nd, 1870.
REPORT OF MR. VAIL.
"BOSTON, August 21, 1869.
"DEAR SIR,--I owe you an apology for not writing earlier, and communicating my observations on the eclipse; but since I parted from you at Detroit, I have been so constantly on the move, as to seem to have no opportunity. I will now state briefly a few phenomena that I noticed at the time of the eclipse, most of which I think were communicated to you verbally before.
"After the clouds that partially obscured the sari on the morning of the 7th had passed away, I observed that though the atmosphere was hazy, and the sky by no means blue, there was an unusual stillness and freedom from agitation in the air, so that the outlines of the spots on the sun were clearly defined in the small Dolland telescope that I had under my charge, and this satisfactory condition of the air for telescopic observation continued until after the end of totality. The first contact was at 3h. 38m. 10s local time. It was probably about 3s. after this, before you were notified that the eclipse had begun, two or three seconds being lost in determining whether it was the limb of the moon, indenting the edge of the sun, or not. Your first photograph was therefore probably five or six seconds after the beginning. The passage of the edge of the moon over the larger spot on the sun, I noted as follows:--
H. M. S. Contact with the Penumbra................. 4 3 34 " " " Umbra.................... 4 3 56 Complete obscuration of Umbra............. 4 4 34
The general phenomena, such as the darkness, the shining of the stars, &c, I had less opportunity of noticing than yourself and others, who were without a telescope, and will therefore say nothing about them. I have made no attempt to put my observations into any regular form, but have hastily written such as I thought might be of use to you, leaving it entirely to you to make any use of them.
MR. FALCONER'S OBSERVATIONS.
"Dear Sir,--As requested by you, I now give you the results of such observations as were made by me on the 7th of August last, during the progress of the eclipse.
The limbs of the moon could be clearly defined beyond the S. and S.E. limbs of the sun. Shortly before totality, there appeared on the sun's northern limb several watery-looking globules, which merged into each other as they passed from West to East, and then disappeared. At this instant, also, appeared distinct long, brilliant, yellow, rays of light, running East and West, and far away, and as straight as if ruled; others again ran North and South, and reminded me of the glory ancient painters depict around the heads of Saints. On the Southern limb appeared, just at totality, a large circular opening, or ring of bright silvery light, which assumed the shape of a red-hot crooked bar of iron. This, resting on the dazzling silvery coronal light, gave a strange and wondrous addition to the glorious scene we now beheld. Several constellations shone brightly fourth, and a star or two low down on the Western horizon. I must not omit the strange protuberances seen at this moment: on the Eastern side was one like a tongue bent upwards, with streaks of a reddish hue; the others the shape of knobs, dark and colorless, and rugged in outline.
"I now come to the general appearance of the land and sky, and the changes that took place over the vast prairie, stretching far and wide, upon which you had erected your observatory. It was long before any appearance of gloom or darkness occurred, not till 4h. 29m., when a hazy gloom gradually spread over the broad expanse which surrounded us. At 4h. 34m. was seen a dense cloud approaching from the N.W. and S.W., rolling along in its course and obscuring everything around. Indeed, it had the appearance of a coming storm, and seemed in part to issue from the prairie. It did not reach or envelope the observatory. In front of this was a lurid, unearthly glare, clear and bright, of a greenish tinge; the dense prairie grass around might have contributed to this effect. Presently, when totality took place, all became comparatively dark; every tongue was hushed amongst the groups of persons who had come out on foot, or were seated in their waggons, from Jefferson and the country around.
And what did they behold? A wondrous sight! At the moment of totality, burst forth the beautiful coronal light of the brightness of burnished silver! Upon the Southern portion of this ring of light, rested that curved, elongated protuberance, of a fiery redness, rendered more ruddy in contrast with the dazzling silvery light of the corona.
"Several constellations shone bright and clear; several stars also were observed above the Western horizon. All these gave the scene a magnificence and grandeur. Wonder and admiration sat upon every face uplifted to the sky. Every voice was hushed. Sublime, indeed, was the scene presented. In reverential awe the groups stood mute. Each one seemed to ponder within himself over the glorious scene in front of him.
"Presently, the light of the sun suddenly bursts forth; the clouds which covered the vast prairie lift, and gradually roll away. Then along the Western horizon are displayed long bright streaks of light, as seen at the approach of coming day. The purple hue upon the distant prairie vanishes. The stars also disappear, and the momentary night is turned into day!
"A murmur is now heard, and voices arise, proclaiming the sublimity of the scene they had just witnessed, one of the most wondrous and imposing sights presented to the human eye, in the firmament of heaven! The words of the Psalmist involuntarily fell from the lips: 'The heavens declare the glory of God, and the firmament sheweth his handiwork.'
"At the approach of totality, the station-master informed me his poultry quietly went to roost. In Jefferson City, the swallows flew down upon the ground, amidst the granite boulders, and remained till the light returned, when they arose and flew wildly about.
"It remains only for me, in conclusion, to thank you and Mr. Douglas for inviting me to join this highly-interesting expedition, and to congratulate you and Mr. Douglas upon the great success which attended your photographic operations.
"I have to thank you for beholding the wondrous and vast prairies west of the Mississippi. 'Haec olim meminisse juvabit.'
"I remain, dear Capt. Ashe, yours very faithfully,
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