A CATALOGUE OF OBSERVATIONS OF LUMINOUS METEORS. 143 



soon with the naked eye. In the specti'oscope, two images of the meteor and 

 of the streak were visible, one refracted, and one accidentally reflected at the 

 side. These two images of the meteor and of its streak could not be distin- 

 guished apart, at least in their general appearance, — the conclusion beiug that 

 the hght, both of the nucleus and of its luminous streak, was homogeneous, 

 and that its luminous suhstance was a gas. 



" No. 3, 0'^ 42'" A.M. A very brilliant fii-eball with a flash like lightning 

 biu'st overhead, leaving a streak from 6 Cygui, halfway to a Lyra, for twenty 

 seconds. A cloud unfortunately dimmed the streak. In the spectroscope, 

 as far as cloud would permit any judgment of the streak to be formed, its 

 aspect was the same as to the unassisted eye. The light of the streak was 

 therefore probably homogeneous, and the strealc itself prohaUy a luminous gas. 



" No. 4, 1'' 15™ A.M. About equal to a second-mag. star. Shot in three- 

 quarters of a second from 6 Cassiopeiae, halfway to o Honorum, and then 

 turned round the quarter of a ciixle to u Honorum, where it vanished, leav- 

 ing a streak for half a second on its course. In the spectroscope, the general 

 appearance of the meteor and of the streak in the field of view was the same 

 as that of the purely reflected image by the side, — the conclusion being, as 

 before, that the light, both of the meteor and of the streak, was homogeneous, 

 or that the luminous substance of the meteor was a gas. 



" No. 5, 1*^ 40" A.M. About equal to a second-mag. star. Passed slowly 

 through a short path near (d Tauri, directed from Cassiopeia ; duration one 

 second, leaving a streak at the place for three seconds. The spectrum of the 

 meteor and streak was qiiite equally diffused over a space about |° in width ; 

 its colour greyish white ; the diffuse train-spectrum vanished without further 

 change, — the conclusion being that in this case tlie train might, like the nuclem, 

 he composed of heated sparks. 



" No. 6, 2^ 15™ A.M. Equal to a first-mag. star. Shot on the same course 

 as No. 2 ; duration one second, leaving a bright streak for four seconds. The 

 spectroscope was turned towards the streak before it disappeared. The train 

 was widened by the prisms to a greyish-white band, somewhat greater than 

 a quarter of a degree in breadth. It faded from sight without further change, — 

 the conclusion in this case also being that the train might possihly he composed 

 of heated sparks. 



" Three spectra in the foregoing observations appeared homogeneous, like 

 that of a luminous gas (Nos. 2, 3, 4) ; and three were continuous or diffuse 

 (Nos. 1, 5, 6), like that of an ordinary spark. The question, accordingly, 

 whether luminous meteors might or ruight not contain solid substance, re- 

 mained undecided, when daylight beginning to appear put a stop to further 

 observations. 



" The following night observations could fortunately be resumed ;, and the 

 perplexing appearance of the meteor-spectra on the previous night received a 

 truly surprising and most satisfactory explanation, in the repeated aj^pear- 

 ance in the spectra of the streaks of a yellow line, unmistal-eahhj that of the 

 metal sodium in comhustion. 



" Two observers being'engaged to watch on this night, one checked the ob- 

 servations of the other with the naked eye. The troublesome reflected image 

 in the spectroscope could accordingly be dispensed with, and it was kept out 

 of sight ; so that the views obtained of the meteor-spectra came as nearly to 

 perfection as could be wished. 



" August 10th, continued. — No. 7, 4^^ 22"" p.m. Equal to a first-mag. star. 

 Shot from y Cephei to I Draconis in three-quarters of a second, leaving a 

 bright streak for five seconds on its course. The meteor first appeared in the 



