26o RECREATIONS OF A NATURALIST 



was filled with the warbling cry of the Larks ; now 

 and then a Thrush was heard ; and once a Heron 

 screamed as it passed by. The night was starless, 

 and the town was invisible ; but the island looked 

 like the outskirts of a gas-lighted city, being 

 sprinkled over with brilliant lanterns. Many of 

 the Larks alighted on the ground to rest, and 

 allowed the Heligolanders to pass their nets over 

 them. About 3 a.m. a heavy thunderstorm came 

 on, with deluges of rain ; a few breaks in the clouds 

 revealed the stars, and the migration came to an 

 end, or continued above the range of our vision."^ 



In giving similar testimony to the effect so 

 graphically described by Mr Seebohm, the light- 

 house-keepers on our own shores confirm what has 

 been known almost since the world began (for do 

 we not read in Scripture that birds " have their 

 appointed seasons " ?) and state that the coming and 

 going of certain species at particular periods of the 

 year may be looked for and observed with singular 

 regularity. This remarkable habit is termed 

 " migration," and notwithstanding that few natural 

 phenomena are more familiar, none perhaps still 

 remains so shrouded in mystery. The migration 

 of birds has attracted the attention of observers in 

 all ages and of all nations, yet few questions in 

 ornithology are more difficult of solution than the 

 problem " Why and how do birds migrate ? " 

 what innate force impels them seasonally in a 

 particular direction ? and how do they find their 

 way ? Before attempting to suggest answers to 

 ^ Siberia in Europe, p. 256. 



