PHOSPHORESCENCE. 4,9 



candles at the distanceof 95,000,000 of miles, which 

 is our distance from the sun. Hence it follows, 

 that the amount of light which flows from the sun 

 could scarcely be produced by the daily consump- 

 tion of 700 globes of tallow, each equal to the Earth 

 in magnitude. 



It does not follow that because planetary bodies 

 shine principally by borrowed light, that they do 

 not possess also a certain amount of phosphoric 

 luminosity. Some modern philosophers are in- 

 clined to believe that our earth itself has a peculiar 

 phosphoric light of its own : 



(< The extraordinary lightness of whole nights in 

 the year 1831," says Alex, von Humboldt, " during 

 which small print might be read at midnight in 

 the latitudes of Italy and the north of Germany, 

 is a fact directly at variance with all that we know 

 according to the most recent and accurate re- 

 searches on the crepuscular theory and the height 

 of the atmosphere." (Cosmos, i. 133, 134.) And, 

 again in the same beautiful work (p. 197), when 

 speaking of the Aurora Borealis : ' ( This beautiful 

 phenomenon derives the greater part of its im- 

 portance from the fact that the earth becomes 

 self-luminous, and that as a planet, besides the 

 light which it receives from the central body the 

 Sun, it shows itself capable in itself of developing 

 light." The intensity of the light thus diffused is 

 often superior to that shed by the moon in her 



