82 eepoet — 1879. 



it is therefore shortened, but the average time of flight observed at 

 Birmingham and Blackheath, being at the same time less than that 

 observed at Birmingham alone, the calculated real velocity still remains 

 about 12 or 15 miles per second, which very nearly agrees with the 

 parabolic speed, about 13 miles per second, of a meteor from the actual 

 radiant-point. The position of this point is at 177° + 49°, and Heis' 

 shower-apex, M 7 for April 1-15 is at 180° + 49°, so close to the observed 

 position that another example is afforded by this double observation, of a 

 detonating fireball proceeding from a known centre of divergence of 

 ordinary shooting-stars. 



1878, August 11, 10 h 10 m p.m. (Indianapolis time) ; West Virginia 

 and Pennsylvania, U.S. — Descriptions of this meteor at three points in 

 the centrarpart of the United States, collected by Professor Kirkwood, 

 enabled him to deduce approximately its real course. At Bloomington, 

 Ind., it shot northwards some 20° in the east with a track slightly 

 declining downwards from alt. 10° at first appearance in the east. 

 By a rough estimate the time of flight scarcely exceeded two seconds. At 

 Titusville, Pa., in that direction, near the point of concourse of the 

 three States of Pennsylvania, Virginia, and Ohio, the meteors shot 

 northwards in the west, lighting up the country more strongly than the 

 full moon, with a greenish light, bursting at last into one large, and 

 two red fragments, and giving rise to a report like thunder heard at an 

 interval after the fireball's disruption corresponding to a distance from 

 Titusville of 25 miles. The meteor also moved from south to north over 

 Oil city, Venango County, Pa., a meridian through the western boundary 

 of which county must have been the projected direction of its course upon 

 a map. This real course is 348 miles east from Bloomington, so that the 

 meteor's probable elevation at first appearance was about 77 miles over 

 the northern part of West Virginia, and 160 or 175 miles from the place 

 of final disruption of the fireball into fragments west of Titusville. The 

 duration there of its illumination was 'momentary,' so that the only 

 recorded estimates of its time of flight seem to denote a real velocity 

 much greater than would correspond to original motion of the fireball in 

 a parabolic orbit. The radiant point of the adopted real path is about at 

 292°-31° ; but if (as is quite possible) the real path's geographical pro- 

 jection was considerably inclined to the meridian, its radiant was then 

 at some point of a great circle of the heavens passing through this 

 adopted place and through a point on the equator at about R.A. 10°. 



1878, November 18, 9 h 50 m p.m. — Besides the determination of this 

 small fireball's real course (seen by Mr. Corder and Mr. Denning at 

 Writtle and at Bristol) by Professor Herschel, in the ' Observatory,' * 

 where the original observations of its appearance are given as described 

 in the accompanying fireball list by Mr. Denning, the real height and 

 position of its course were independently calculated by Major Tupman 

 with results which were not at very great variance with those already 

 published. The height, position, and extent of the fireball's real path 

 have now been reinvestigated by Major Tupman and Professor Herschel 

 on the assumption that the short arc which it appeared at Bristol to 

 describe, was but the end-part of a much longer flight, the whole visible 

 extent of which was equally well seen and mapped at j Writtle by 



origin of the meteor's course is now 15 miles west from Eockingham, and nearer 

 Coventry, over a point about 10 miles due south from Leicester, 

 i Vol. ii. (1878-79), p. 306. 



