INTRODUCTION. 



IT has long been known that the little island of Heligoland, 

 in the North Sea, is a spot especially favoured as a place of call, 

 by passing birds during their long migrations to and from their 

 breeding grounds. From time to time items of news, in the 

 shape of short notes, relating to the island, or the account of 

 a visit made by some enterprising ornithologist, have appeared 

 in the current ornithological journals, from which some idea of 

 the marvels of the place might be gathered. But at no time 

 has any attempt been made by a resident on the island itself, 

 to give a detailed account of the volume and character of the 

 migratory phenomena to be witnessed there. It has, however, 

 been no secret that one, with whose name that of Heligoland has 

 long been associated Herr Heinrich Gatke, has been for many 

 years accumulating material for such a work. 



The appearance of "Die Volgelwarte Helgoland," printed in 

 the German language, some four years ago, was hailed with 

 universal welcome, and in response to a unanimous demand an 

 English translation was published early in 1895. 



In a volume replete with interest, special prominence will be 

 found attaching to the author's opinions expressed in the leading 

 chapters relating to the direction, attitude, velocity, order, guid- 

 ing power, and meteorological conditions affecting the migratory 

 flight. The remainder of the work being chiefly occupied by 

 notes on the various species visiting the island, under their 

 separate headings. 



No one has perhaps more closely studied, or had better 

 opportunities for the observation of the different phases of 



