On Crag and Sea-cliff 239 



must be many thousands of nests of this bird in 

 the dales of North Derbyshire alone — a profoundly 

 interesting" fact, which indicates that such situations 

 were invariably selected in prehistoric times before 

 such thino-s as houses and bridoes were in existence. 

 Talkinof of bridges brinsjs to mind the fact that on 

 some of the railway viaducts in these dales the 

 copings are so thickly studded with nests in some 

 places as to hide the mason r). We ought also 

 to mention that the Kestrel breeds commonly in 

 these limestone crags, and not a few Redstarts and 

 Wheatears have their homes in crevices among 

 them, at a lower level and near the ground, of 

 course. Swifts are equally common, and in their 

 choice of a haunt suororest a habit that has been 

 retained from a remote period, although changed by 

 many individuals in more recent times. We might 

 also mention that the Peregrine Falcon still breeds 

 locally on some of these inland crags of the northern 

 shires, especially in the Lake District. 



So far the inland crags; we will now proceed to a 

 study of the bird-life on the sea-cliffs of the north. 

 It is in these localities again that the northern shires 

 show to advantage over most southern counties in 

 the matter of their bird-life. Nowhere in the south 

 can be found such vast bird bazaars as those that 

 are established in such wonderful abundance upon 

 the sea-cliffs of the northern shires. From York- 



