268 BIRDS OF NOKFOLK. 



midst of a rookery, as may be seen by any traveller 

 on tbe line, without materially decreasing the number 

 of nests on either side. It is not improbable, I think, 

 that birds possessed of such known sagacity may 

 be also forewarned of the instability of old timbers, 

 as rats are said to leave a falling house; and the 

 thinning out of some of their favourite trees by any 

 heavy gale, may determine them to seek fresh quarters, 

 or to leave those trees most affected by the wind. But 

 though often shifting their quarters of their own accord, 

 it is by no means easy to drive them from some long 

 accustomed haunt. The common practice of shooting 

 the young birds with rifles and air-canes, when pursued 

 in moderation, has by no means a tendency to diminish 

 a rookery, whose surplus population if spared by man, 

 would only be driven to a distance to found new settle- 

 ments. The noisy use of shot guns is, of course, 

 objectionable as well as unsportsmanlike, but I beheve 

 the only effectual plan of exterminating these birds, if 

 desired — and I can scarcely imagine any one so devoid 

 of all appreciation of rural sights and sounds as to 

 attempt such vandalism — is the constant disturbance of 

 the old ones whilst sitting, by which means the eggs 

 are destroyed from frequent exposure to the cold. The 

 difficulty also of inducing them to build in some fresh 

 locality is well known, the placing of old nests in 

 the desired trees, or where possible, the substitution of 

 rooks' eggs, for those of carrion-crows or magpies 

 having often failed after repeated trials. Mr. Newcome 

 has, however, succeeded in establishing a very respect- 

 able rookery in the trees round Hockwold Hall, which 

 he effected by first of all substituting rooks' eggs for 

 those of the jackdaws in the nests of the latter. Though 

 for the most part selecting the tallest trees, and placing 

 their nests near the upper branches, they will build also 

 on low Scotch firs, in the most exposed situations. A 



