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MEMOIKS OF THE NATIONAL ACADEMY OF SCIENCES. 



OBSERVATIONS OP THE CONTACTS. 



In observiug tlie four contacts of the solar eclipse a small telescope of 3i inches aperture 

 was used. A magnifying power of about 100 was used. I took my place at the telescope 

 three minutes before the computed time of flr.st contact, directed it towards the sun, and 

 verified the adjustments which had been made some time previously. The definition was found 

 to be perfect, the atmosphere was clear, for we had had a heavy rain shower 40 miuutes before, 

 and the image of the sun steady. The sun was placed near the center of the field, and then a rest 

 of one minute was taken before beginning to look. The point of the sun's limb at which the moon 

 was to ajipear was watched eagerly, as was also an arc of probably 10° on either side. When the 

 computed time was uj) and no moon was seen, I still glanced at the piedicted point once every 

 second, but widened the arc so that any indentation in the sun's limb would be detected within an 

 arc of 20° on either side. Fifteen seconds after the computed time I thought 1 noticed a change 

 in the appearance of the sun's limb, and one and a half seconds later, noted by a sounder at my side, 

 I became convinced that I was looking at the moon's advancing limb and instantly made a signal, 

 which was registered on the chronograph chronometer Negus 1589, at l"" 0"" 33.3". This made 

 the time of first contact at 1'" 00™ 31.S». Negus 1589 was keeping very nearly local sideral time. 

 No roughness was noticed on the moon's limb either at first contact or soon thereafter, and no inti- 

 mation of her presence was had before she impinged upon the sun's limb. At 2'» 8™ we noticed the 

 first appearance of decided gloom. In the east the horizon appeared as it does late at sunset, with 

 a yellowish tinge, which deepened and became darker until totality set in. Mr. W. B. Fletcher 

 was calling aloud the minutes of time to elapse before the computed time of second contact, and 

 when he called "Two" I again took my place at the telescope. The visible portion of the sun was 

 now reduced to a very thin crescent, and at 2"' 28"' 18» Baily's beads first appeared. At this mo- 

 ment they were seen only at the southern point of the crescent. It was not until 2'' 28'" 52" or 

 O.J seconds before second contact that they v/ere seen in profusion. Second contact was noted at 

 2'> 28'" 58.5». 



During the 300 seconds immediately following second contact I was engaged in polari.scopic 

 observations. At the end of this time I returned to the telescope. At 2'' 34™ 11.9% the red chro- 

 mosphere was quite apparent on the west of the moon. This was noted on the chi-onograph by a 

 peculiar signal, to avoid mistaking it for the third contact signal. The color of the chromosphere 

 grew more and more intense as the time elapsed until at 2'' 34'" 24.0' the first ray of true sunlight 

 appeared, which was as unmistakable in its character as the flash of a spark of electricity. 

 Coming after the darkness of a long totality it reminded one strongly of the outburst of an electric 



