164 THE WONDER OF LIFE 



the coast of Cornwall, for instance, one recalls Tennyson's 

 picture 



Faint as a climate-changing bird that flies 

 All night across the darkness, and at dawn 

 Falls on the threshold of her native land, 

 And can no more. 



But whether the migration be seen in a striking or in an 

 inconspicuous form, it can never fail to produce the thrill 

 of wonder in the reflective observer. 



Lines of Inquiry. It may be said broadly that there 

 are three main lines of inquiry, each reasonable and promise- 

 ful. Each has indeed already led to important results. 

 First, there is the method of registering the arrivals and 

 departures, the changes and movements, in a small area 

 like Heligoland or Fair Island, which can be thoroughly 

 explored. We cannot mention these two islands without 

 thinking at once of Gatke and Eagle Clarke. Second, 

 there is the method of collecting data, year after year, from 

 observers scattered over a wide area, both inland and on 

 lighthouses and lightships, who record times of arrival 

 and departure, great wave-like incursions, marked increase 

 and decrease in numbers, and the like. This is the method, 

 painstaking and laborious, and sure to yield generalizations 

 in the long run, which has been followed for eight years 

 now (1914) by the British Ornithologists' Club. Third, 

 there is the method, which we may particularly associate 

 with the name of Dr. Thienemann of Rossitten, of marking 

 large numbers of migrants with indexed aluminium rings, 

 in the hope of hearing again of the whereabouts of a small 

 percentage in their winter-quarters or summer- quarters 

 or en route between the two. This method has already led 

 to the mapping out of a more than provisional migrational 



