88 REPORT— 1870. 



Michigan, was ninety-eight miles above the earth, and the first inflection of its 

 conrse, nearly over Dansville, New York, took place at a height of fifty-six 

 miles, and the second, nearly over New York, at thirty-nine miles above the 

 sea. The last place where the meteor was well observed was at Germanstown, 

 Pennsylvania, and the meteor was then fifty-three miles above the level of the 

 sea, in long, about G8|° west from Greenwich (at b, fig. 6). Finally, at 

 Harrisburgh, Pennsylvania, it was still visible in the east, in longitude about 

 00° west from Greenwich ; and its height was then rapidly increasing, and 

 was again upwards of sixty miles above the sea-level. 



The meteor pursued its course with a velocity, relative to the earth, of about 

 nine and three-quarter miles per second, experiencing throughout its aerial 

 track a small but scarcely appreciable resistance from the atmosphere. With 

 a relative velocity somewhat less than this it entered the sphere of the 

 earth's dominant attraction from the direction of a point in E. A. 147° 41', 

 N. Decl. 3° 8', and it was deflected before escaping from the disturbing 

 influence of gravity towards the earth fully 35° from its original direction. 

 The circumstance of its slow velocity relatively to the earth introduces com- 

 plexities in determining the real orbit of the meteor round the sun, which it 

 would yet be interesting, from the elaborate calculations to which the ob- 

 servations were submitted, and from the unusual accuracy with which the 

 elements of this great meteor's path have accordingly become known, to ascer- 

 tain with every possible degree of approximation to the most probable result. 



The long course and duration of the flight of the large meteor doubly 

 observed on the 12th of December, 1869 (see the First Appendix), furnishes 

 a good example during the past year of a shooting-star belonging to a 

 periodical meteor-stream grazing for a long distance, without being consumed, 

 the summit of the earth's atmosphere, and suggests as a favourable means of 

 ascertaining their velocity, the propriety of observing their parallax when the 

 radiant-point of a meteoric shower is scarcely risen, or presents itself, as in 

 the case of the great meteor of July 1860, at only a few degrees of altitude 

 above the observer's visible horizon. 



1869, May 20th, a few minutes after 11" p.m. (local time), United States. 

 The meteor, which appeared brighter than the full moon, was seen at many 

 places in the United States (vide Amer. Journal of Science, July 1869) re- 

 maining visible for about five seconds, drawing behind it a very brilliant tail 

 of sparks, and finally exploding and bursting into fragments, apparently with 

 a loud report. From observations at New York, Poughkeepsie, Newhaven, 

 and Hartford, U.S., of its apparent path. Prof. E. Loomis has determined with 

 considerable precision the length of the meteor's real path and its real eleva- 

 tion. The meteor moved nearly horizontally at a height of fifty miles above 

 the earth's surface, disappearing, after a visible course of about 200 miles, 

 vertically over a point on the Atlantic Ocean somewhat north and east of 

 Eoston. The real velocity of its motion, assuming its time of flight to have 

 been five seconds, was about forty miles per second. About three minutes 

 after the passage of the meteor a terrific noise was heard in the neighbour- 

 hood of New York, which shook windows and the doors of houses like an 

 earthquake. As Prof. Loomis shows that the meteor was at the time of its 

 explosion 170 miles distant from places where the unusual sounds were heard 

 so soon after its disappearance, it is supposed that they must accordingly be 

 ascribed to some other cause than this large meteor, the sound of whose re- 

 port, would occupy ten minutes in reaching them, with the ordinary velocity 

 of sound in common air. 



1869, August 7th and 24th, evening. United States. The following de- 



