2 STUDIES IN BIRD-MIGRATION 



undertaking some researches regarding them. To 

 accomplish this, however, it was essential that I should 

 spend some weeks on board one of the lightships — a 

 course which demanded some consideration, since life on 

 one of these floating observatories is inseparable from 

 discomforts peculiarly its own. Encouraged, however, 

 by the experience gained at the Eddystone lighthouse in 

 the autumn of 190 1, I decided to make the venture, and 

 an application was forwarded on my behalf by the Royal 

 Society to the Trinity House for permission to spend a 

 month during the autumn of 1903 on board one of 

 the Corporation's lightships in the North Sea. This 

 privilege was graciously granted, and every facility was 

 offered for visiting any vessel that might be selected. 



The selection of a suitable station demanded careful 

 consideration, and I finally decided upon the Kentish 

 Knock lightship. This vessel appeared to me to lie at or 

 near the centre of the migratory stream that I desired to 

 investigate, and its remote situation, out of sight of land, 

 promised to afford an excellent opportunity for witnessing 

 the various movements, and the conditions under which 

 they were performed, free from the Influences which 

 might prevail at stations nearer to our shores ; lastly, 

 the character of its light, a most important factor, 

 seemed to be especially adapted for attracting the 

 migrants which might pass in the night. 



The geographical position of the lightship will be 

 best realised by a reference to the map on page 4, 

 which shows its situation In relation both to the 

 English shores and those of the Continent. It Is 

 stationed in latitude 51° 38' 50^^ N., and in longitude 

 i 39' 55^' E., lying 21 miles north-east-by-north of 

 Margate, and 21.5 miles south-east of the Naze, which 



