Apparent Visibility of Stars through the Moon. 137 



Peebles-shire, and that they outlived their translation through- 

 out a period of at least seven years. 



The late distinguished zoologist Sir John Graham Dalyell, 

 Bart., instituted, at my request, a series of inquiries for the 

 purpose of ascertaining if the descendants of this stock were 

 still to be found in the places referred to, but all traces of such 

 animals had disappeared, and even tradition, usually a toler- 

 ably faithful record, had preserved no memorial of the ex- 

 periment. 



It would be a very easy process at the present time, with 

 the command of railway speed, to transport the animals from 

 their native haunts to any of our suitable streams ; while such 

 an addition to our luxuries would not interfere with any 

 other source of enjoyment. 



Pennant, in his " British Zoology," terms the crustacean 

 CuAW-FiSH ; but Berkenhont and later writers term it Cray- 

 Fish. J. F. 



New College, Edinburgh, 

 3d December 1853. 



On the apparent Visibility of Stars through the Moon imme- 

 diately before their Occultation. By R. Edmonds Jun., 

 Esq. Communicated by the Author. 



Eight years ago, when the cause of the occasional projec- 

 tion of a star on the moon's disk for a few seconds before its 

 occultation was, at one of the meetings of the British Associa- 

 tion, and elsewhere, publicly discussed by eminent scientific 

 men, I prepared a short paper, suggesting that it might arise 

 from the telescope being on such occasions set to the star's 

 focus instead of the moon's, in which case the imperfect image 

 of the moon formed at the stellar focus would, of course, be 

 magnified. But when the star is on the very edge of the 

 moon, the image of the latter would not find room for being 

 magnified without spreading itself over the star's image, and 

 thus occasioning the apparent visibility of the star through 

 the moon, the extent of this projection being equal to the 

 excess of the radius of the magnified lunar image beyond that 



