MIGRATION. 267 



recess of these creatures, and serve for little else but 

 their entertainment. 



" Thus we see many rocky islands in the sea that 

 are of no other manifest use than for sea-fowls to rest 

 and breed upon, and these are therefore commonly 

 called Gulrocks. Now if there be such globules (or 

 etherial islands) they must be supposed of such 

 magnitude only, and set off at such distance as their 

 reflective light may not reach home to our earth 

 (though perhaps they may serve to illuminate our 

 atmosphere), else they would ere now have been dis- 

 covered, and yet no farther off than these birds may 

 conveniently arrive unto them in such time as may 

 be most convenient to allow them. This I do sug- 

 gest, because it is as hard for me to persuade myself 

 that they come from any other part of this earth as 

 it is to persuade another that they come from the 

 moon, and therefore if the moon will not be allowed, 

 some other place must be found out for them *." 



This notion, extravagant as it appears to be, was 

 discussed by the celebrated Ray and his correspon- 

 dents ; but, as might have been expected, it was 

 decided by them that the moon is too far off to be 

 reached by our migratory birds. 



* An Essay towards the probable Solution of this Question, 

 Whence come the Stork, &c.; or where those Birds do probably 

 make their Recess, &c. 12mo. Crouch, London, 1703. 



