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The line of progress of the axis of this storm, after leaving Turks Island, seems to have been almost identical with that of the Antigua Hurricane of Aug. 22, 1848, which also passed over the Bahamas, beginning its easterly recurvature also about latitude 28° or 29°, and pursuing its northeasterly track at least to long. 35° and lat. 45°, occupying twelve days in its journey.
The numbers upon the little chart refer to the places named in your Abstract of Observations, as well as to those of Capt. Stuart's table. With great respect, I have the honor to remain, Your obdt. servant,
John H. REDFIELD.
BAHAMAS HURRICANE OF OCTOBER, 1866,
Showing directions of wind at noon, Oct. 1.
W. H. STUART, BAHAMAS.
Art. X.-Meteors of November 14th, 1868.
On the morning of Saturday the 14th of November, 1868, there was another recurrence of he November star shower. The following are the accounts of the numbers and appearances of the meteors as reported from different places.
1. At New Haven.—The writer, with Mr. O. Harger, and several students in the College, watched from the top of the tower of Graduates Hall. We commenced counting as the clock struck twelve. There were at first seven or eight in the party, but within ten minutes this number increased to about twelve who were counting. Toward morning the number diminished to seven or eight. To each person was assigned a direction to which he was to look. From our station we had an unobstructed view of the heavens.
The counting was aloud to avoid duplication ; each meteor, whether seen by one or by several persons being counted once and once only. Such at least was our aim, and probably few were lost at first. But after a time as the meteors became more abundant it was evident that many were lost in the counting. For, when two or three came nearly or quite at the same instant, only one might be added to the number. We were then by no means certain that we were making a fair census. I directed each one, therefore, to count silently during intervals which I carefully limited by the watch. The numbers reported by each observer during these intervals were entered upon the record. Immediately upon the close of an interval the counting in concert was resumed.
In the first table given below there are in the first column the intervals of observation during which we were counting in concert; in the second column the lengths of those intervals; in the third column the numbers actually counted in the interval; in the fourth the average number per minute; in the fifth the number of observers; and in the sixth the total number
In computing these hourly numbers, allowance is made for the omitted intervals by assuming for the rate per minute the half sum of the rates of the periods just preceding and following. In the four hours and forty-two minutes the numbers counted amounted to 5573. For the omitted intervals the above rule gives 1786, making a total of 7359 in the six hours.
In the second table are the numbers seen by each observer in the corresponding specified intervals. The average numbers per minute for each observer are given in the final column.
TABLE I.-Showing the numbers of meteors seen at New Haven in successive inter
vals, on the morning of Nov. 14th, 1868, by the whole party observing. Interval of observation.
Duration, Number. No. per min. No. of obs. Hourly No. From 12h Om to 12h 15m
130 12 757
79 15.8 12
129 25.8 11 1132
101 25.2 11
109 21.5 11
111 22:2 11
108 21.6 11
11 1369 3h 07m“
160 20-0 11
504 21 59 23-6
1335 4h 3m
101 24 41 16:4
1402 Total in 4h 42m, 5573; in six hours, 7359.
TABLE II.-Showing the numbers of meteors seen in New Haven in the intervals of
time named, on the morning of Nov. 14th, 1868, by single observers.
• ! Perry.
a | Maynard.
Av, no. per
8.0 4.0 7.8 8.2 5.9 56 101
ih 48m to lb 49m 2h 2m
12h 5m 231 25 33
35 3h 3m 13 5m 12
38 41 461 48 505
53 551 58 4h 0fm" 4h 3m 103
58 5h 3 18
23 254 301 331
7 5 10 13 5 12
91 23 18
4 8 01 4
30 37 54 58 66 60 83
11.7 8.1 7.3 8.2 63 4.8 7.8 8:0 9.8 9.9 8.8 10.9 11.1 103 6.2 3.6 2.7
" 5h 7m
The short duration of the shower seems to imply that the radiant is very narrow perpendicularly to the ecliptic. Early in the morning hours it seemed that this area must extend parallel to the ecliptic nearly up to & Leonis. But its length in that direction had then to be determined by flights that were nearly parallel to the horizon. The eye cannot easily make allowance for the curvature of the arc of a great circle in carrying backward the line of such a track. I feel sure that the tendency to make such tracks parallel to the horizon is so strong that in a careful location of the radiant, we must reject nearly all those in which the meteor first appears several degrees from the sickle. Yet after all allowances I believe that some paths in these early hours would when traced backward pass near & Leonis. After the radiant had reached an altitude of 30 or 40 degrees, there were very few tracks, if any, which traced back would not cut across the line joining y Leonis with the sixth magnitude star (230 Piazzi, 3423 B. A.C.) in the center of the bend of the sickle, and between these stars.
But there were many tracks which when extended backward cut this line at large angles and near either extremity of it. This implies that the radiant was not much shorter than the distance between them. The latitude of the radiant I estimated as about that of y Leonis, or 81. To determine this latitude only meteors starting from near the radiant and moving nearly parallel to the ecliptic were noticed.
If the radiant was a point, any two well observed flights would determine its place. But in consequence of its considerable length, only flights nearly parallel to, or nearly perpendicular to, the ecliptic are convenient for determining its latitude, and its limits in longitude.
The prevailing tint of the trains was green, or bluish green. Mr. Harger counted 60 unconformable meteors during the six hours. These were strikingly unlike the conformable ones, giving usually the impression of a harder nucleus, and leaving no train.
Many trains were visible for several minutes, and one remained for 44 minutes. They usually floated to the northward.
The sky was beautifully clear, and moonless. There was no abatement in the numbers of the meteors until dawn. Throughout the shower the proportion of faint meteors was very small. As a consequence, the most fruitful regions of the sky were nearer the horizon than in August showers. During the forenoon of the 14th, I watched clear portions of the sky for a short time, but saw no indications of the meteors.
2. At Bowdoin College, Brunswick, Me., communicated by Prof. C. G. Rockwood, Jr.-In the count of meteors, I was assisted by Mr. J. P. Gross and a number of students.
The number varied from thirteen to sixteen, being at no time less than thirteen, nor more than sixteen ; the place selected was on the College grounds, where we had a view of the sky on all sides nearly down to the horizon. The night was perfectly clear, the sky being free from clouds.
The display began before midnight, but the party was arranged and the formal count began at 5lm after midnight.
After 1 o'clock the numbers were recorded (by myself) at intervals of five minutes, the numbers seen being given below: