A MONTH ON THE EDBYSTONE 305 



ever, occurred when the birds were crossing from the 

 south to the north, and the wind may have increased 

 after their departure from the shores of France, or they 

 may have passed into an area of higher velocity on 

 approaching the English shores. 



The prevalence of rain is evidently a matter of 

 indifference to the birds. It is otherwise to the would-be 

 observer, to whom it is most welcome, for the beams from 

 the lantern assume additional apparent luminosity during 

 rain, and the migrating birds are decoyed within the 

 range of observation. On clear nights one is' often 

 dependent upon the intervention of a passing shower to 

 learn whether migration is in progress or not, but on 

 such occasions at the Eddystone few birds actually 

 strike the lantern, though many fly around it. 



When fog prevailed no birds were observed, though 

 the luminosity of the rays of light then becomes most 

 intensely conspicuous, while not penetrating beyond the 

 immediate vicinity of the tower. During fog, charges 

 of tonite are exploded every five minutes and produce a 

 terrific report, which must have a decidedly scaring effect 

 on any approaching migrants, if such there be. 



The only emigratory birds observed during gales 

 were the single examples of the Red-necked Phalarope 

 observed on two occasions. Certain other species, such 

 as Skuas and Storm-Petrels, the latter especially, were 

 much in evidence when the weather was unsettled and 

 the wind high. 



An important and interesting point in connection 

 with the'phenomenon of emigration is the hour at which 

 the departing birds set out upon their night movements. 

 This, however, is a very difficult and obscure subject to 

 investigate. No one, so far as I am aware, has ever 

 I. u 



