VI 



of Observation.' Let us follow the surer method, and, in 

 the words of Lord Salisbury in his address to the British 

 Association at Oxford, rather ' make a survey, not of our 

 science, but of our ignorance.' 



It is not my business to criticise in this place the 

 deductions or arguments of our author, but only to point 

 out very decidedly the important nature of a great and 

 good piece of work, which cannot fail to take its stand as 

 an invaluable guide-post to the better understanding, in 

 many directions, of the great problems yet unsolved, con- 

 nected with the Life-history of Birds ; while amongst our 

 wiser naturalists 'it is hoped it may also prove a warning 

 Pharos against the sunken rocks and shoals of undigested 

 theory and speculation. 



It is with all the greater pleasure that I introduce this 

 English translation to such of our British ornithologists as 

 have been unable to master the German text, because, owing 

 to a somewhat misleading article which appeared in the Ibis l 

 after the publication of the original edition, I fear that the 

 importance of Mr. Gatke's work has not been fully realised. 

 The original list from which the said abstract was com- 

 piled is merely the sum of the materials upon which Mr. 

 Gatke's facts were based ; and the important earlier 

 chapters of the book were ignored entirely by the com- 

 piler. These however possess far higher interest, and 

 commend themselves to the appreciative study of ornitho- 

 logists of every country to a much further extent than 

 either the original list or its inefficient abstract. 



Thus it has been that the subject, so ably illus- 

 trated by our author, has been practically a closed book to 



1 List of the Birds of Heligoland, as recorded by Herr Gatke (Ibis, 1892), p. 1. 



