PHOSPHORESCENCE. 47 
which often persists for a considerable time after 
their passage (fig. 5). In his voyage round the 
world, the Admiral de Krusenstern saw one of 
these Aecrolites leave behind it in the sky a 
Fig. 5. 
phosphorescent streak which persisted for a whole 
hour, without sensibly changing its place. (See 
Humboldt: ‘Cosmos,’ vol. i.) |Phosphorescent 
streaks left behind Aerolites not unfrequently re- 
main visible for about a minute. 
We cannot do more than mention here the 
lightning flash,* the Aurora Borealis, the Zodia- 
cal hight, the fire of St. Elmo, the light of fixed 
* On the various kinds of lightning, see Arago, “ Notice sur 
le Tonnerre,”’ in his ‘Huvres,’ or in the Ann. du Bureau des Longi- 
tudes, for the year 1838; Phipson, in the ‘Comptes-Rendus’ of 
the Academy of Sciences of Paris, April 13, 1857; and Du Moucel’s 
brochure, ‘Sur le Tonnerre et les Eclairs.’ Paris: Hachette, 1857. 
