OBSERVATIONS OF LUMINOUS METEORS. 133 



be accepted) to a very widely different conclusion. The point of first ap- 

 pearance was too far from the observers to be very ccrlainly determined; but 

 the length and duration of the flight at Street give a velocity (19*5 miles per 

 second) which does not perhaps exceed the theoretical velocity in a parabolic 

 orbit (12-3 miles per second) with the radiant-point observed more than can 

 be accounted for by the unavoidable errors of observation. With regard to 

 the meteor's appearance, an interesting description of the view obtained of 

 it (apparently in London, as no place of observation is named in the letter to 

 'The English Mechanic,' vol. xxiii. p. 668, September 8, 1876, where this 

 account appears) by Mr. W. J. Lancaster is as follows : — " I saw the meteor 

 of July 25th splendidly at about 2" 1 after 10 o'clock. Its course terminated 

 far above t; Bootis. In fact I fancied that it was higher than e Bootis, but 

 of this 1 could not be positive because my whole attention was upon the 

 meteor. Of one thing I am, however, positive, and that is, that immediately 

 before it vanished it split into two principal nuclei and a quantity of appa- 

 rent nuclei. The two fragments were about j and 3 the size of the original, 

 the larger fragment being the anterior one ; the other fragment vanished 

 first, then the anterior one. The colour before explosion was a magnificent 

 bluish green. In fact it at once impressed me with an idea of its composi- 

 tion. It was as nearly as possible the colour produced by burning magne- 

 sium and zinc with a trace of copper. Some of the fragments burned with a 

 red tint. I did not hear any sound of an explosion." 



1876, August 11, 11" 22 m p.m.— This was a splendid Persei'd fireball, of 

 which the streak remained visible for a few minutes, assuming a serpentine 

 form, and which was visible from Sunderland in the north to Clifton and 

 Somerton in the south of England. The length of the light-cloud was about 

 12 miles, and it must have been fully half a mile in width before it disap- 

 peared, at the height of 50 miles above the earth's surface, 20 or 30 miles 

 northward from Swansea and Cardiff, at which it was deposited. The metcir 

 produced a white lightning-like illumination 'over S. Wales and the whole 

 country in the neighbourhood of the Bristol Channel. No durations of its 

 flight were, unfortunately, recorded by which its velocity might have been 

 exactly ascertained, as the length of its path and the real height and locality 

 of its luminous track were very accurately noted and determined The 

 radiant-point is indicated with some precision, near the usual radian , -point 

 of the August " Persei'ds." 



1876, August 13, 9" 27 m p.m. — The observations of this Persei'd at Bunt- 

 ingford, near Ware, in Herts, and at Folkestone, arc in perfect accordance 

 for the point of disappearance ; but the meteor's oblique descent towards 

 these places makes the distance from them at which it first appeared diffi- 

 cult to decide. The point of first appearance assigned at Oxford (near a Cas- 

 siopeia;) limits the height of the meteor there at 1-10 miles ; but a less early 

 point of appearance by a few degrees at either of the stations diminishes 

 this height to 90 miles over Walton, where the meteor is taken to have first 

 entered the atmosphere. Like the last meteor, although penetrating it to 

 little more than 40 miles above the earth's surface, it gave rise to no audible 

 explosion. 



1876, August 15, 9 h 30 m i>.m. — This fine Aquariad fireball was observed 

 over an extensive area in England, Wales, and Ireland, and in the Isle of 

 Man. It crossed the Irish Channel from St. Bride's Bay, near Milford Haven, 

 to Arklow in Ireland; and the extent of its further flight is imperfectly 

 known from the distance from all the observers in England who recorded it 

 ■which it there attained. At Newtown (Montgomeryshire) in Wales, a news- 



