SCIENCE AND POETRY. 



This is not only beautiful poetry, but sound astronomy. The 

 distances of the stars are many hundreds of millions of times 

 greater than that of the moon, but their actual splendour is in 

 many cases greater than that of the sun. Thus it has been shown 

 by calculations made upon observations which appear to admit of 

 no doubt, that the star Sirius, commonly called the Dog-star, is a 

 sun 146| times more splendid than that which illuminates our 

 system. Its distance, however, is so enormous that the actual 

 light which it sheds upon our firmament is less than the five 

 thousand millionth part of the sun's light. 



Another star, which is the principal one in the constel- 

 lation of the Centaur, has been ascertained to be a sun whose 

 splendour is 2|- times greater than that of ours, but owing 

 to its enormous distance the light which it sheds in our 

 firmament is twenty-two thousand million times less than that 

 of the sun.* 



Sir John Herschel compared the light shed by this star from 

 -our firmament, and found by exact photometric measurement 

 that it was 27408 times less than the light of the full moon. 



12. Shakspeare imputes to the cricket the sense of hearing 



" I will tell it softly, young crickets shall not hear me. 



This was long considered as a scientific blunder on the part of 

 the poet, the most eminent naturalists having maintained that 

 insects in general have no sense of hearing. Brunelli, an Italian 

 naturalist, however, has demonstrated that the cricket at least 

 has that sense. Several of these insects, which he shut up in a 

 -chamber, continued their usual crinking or chirping the whole 

 day except at moments when he alarmed them by suddenly 

 knocking at the door. The noise alv/ays produced a temporary 

 silence on their part. He contrived to imitate their sounds so well 

 that the whole party responded in a chorus, but were instantly 

 silenced on his knocking at the door. 



He also made the following experiment. He confined a male 

 cricket on one side of his garden, while he put a female on the 

 other side at liberty. The moment the belle heard the crink of 

 her beau she showed no coyness, but immediately made her way 

 to him. 



13. The female glowworm, which emits the phosphorescent light, 

 familiar to all who have dwelt in warm climates, remains com- 

 paratively stationary to await the approach of her mate, attracted 



* Lardner's Astronomy, pp. 749, 752. 

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