OBSERVATIONS OF LUMINOUS METEORS. 309 



mine with an amount of probable error, which would only be very small 

 and insignificant, the real eccentricity of its orbit round the sun. 



The whole length of the meteor's path from over Northallerton to the 

 Firth of Forth was 155 miles, but only the last 100 miles of this track 

 (from about over Alston at the junction of the counties of Durham, 

 Northumberland, and Westmoreland) was visible at York. The duration 

 of this part of its flight was six seconds, measured independently by 

 several observers' recollections of it ; and its light was first noticed about 

 three seconds before the meteor itself was seen, which agrees with the 

 first third part of the length of its path in which the meteor was un- 

 observed. Most of the observers give five or six seconds as the time of 

 flight in the part of the meteor's path to which their view of it extended ; 

 and a duration of nine or ten seconds for the whole path of 155 miles is 

 thus probably not far from the real time of passage of the meteor along 

 this length of course. The velocity of the fireball's motion on this com- 

 putation was about 16^ miles per second, while the velocity of a body from 

 the same radiant point, moving in a parabolic orbit, is 15 miles per 

 second. This result conducts us, therefore, to a fairly probable conclusion 

 that the meteor's real orbit was not far from being one of a parabolic 

 form. 



The head of the meteor was round, ending in a tail of moderate length, 

 consisting of sparks, which at a distance seemed red, but among which 

 some bright fragments of other colours were also visible to observers 

 nearest to its track : one of whom described its nucleus as double, and 

 another as ending behind in a long tail as brilliant as itself. Just before 

 its disappearance a fragment, or body of red sparks of considerable size, 

 seems to have detached itself from the head, and it is not impossible that 

 the explosion heard at Galashiels may have been caused by this dis- 

 ruption, of which no sounds are nevertheless recorded to have reached 

 Edinburgh or other places closer to the point of the meteor's final dis- 

 appearance. Though flashes of distant or " sheet lightning " were seen at 

 Galashiels, and continued for some time (unaccompanied it would seem by 

 thunder), about a quarter of an hour after the occurrence of the fireball, 

 yet the sky seems to have been pretty clear at Galashiels at the time of 

 the meteor's passage, and the later occurrence of flashes of distant 

 lightning there appears to offer no sufficient explanation of the " one 

 deep peal of thunder " which the observer of its transit there relates that 

 he heard two minutes after the fireball's disappearance. If the illuminating 

 power of the nucleus was very great, the strength of the light which it 

 cast is not expressly noticed by any of the writers who described it, but 

 it may be presumed that near Edinburgh, where its apparent diameter was 

 about one-sixth of that of the moon, its light must have been sufficient to 

 cast observers' shadows on the ground. At York its apparent brilliancy 

 was described as almost equal to that of the planet Venus. The nucleus 

 emitted no sparks, but split into two at the end, one part about ^° in 

 advance of the other when they both disappeared, apparently, behind a 

 thin cloud that stretched above some trees near the N.W. horizon. 



1878, June 7th, 8 h 30 m , and 9 h 53 m p.m. large fireballs, Devonshire, 

 and the south of England. — Two fireballs, of which the second was much 

 the largest, passed across the south-west part of England, both remarkable 

 for their long courses and slow flight, on the evening of this date. 

 Mr. Lighton's observation of the first (see the catalogue for the full 

 descriptions of the courses and appearances) gives the point of the horizon 



