266 Wild Lifein a Southern County. 
that it will always be so. At last the rooks desert it, 
and then the truth is apparent. 
Their nests, being heavy, are not safe on branches 
up which the strengthening sap no longer rises ; and 
in addition to the nest there is the weight of the sit- 
ting-bird, and often that of the other who perches 
temporarily on the edge. As the branches die they 
become stiff, and will not bend to the gale this im- 
mobility is also dangerous to the nest. So long as 
the bough yields and sways gently—not much, but 
still a littlke—the strong winds do no injury. When 
the bough becomes rigid, the broad side or wall of 
the nest offers an unyielding surface, which is accord- 
ingly blown away. 
The nests which contain young are easily distin- 
guished, despite the height, by the almost continuous 
cry for food. The labour of feeding the voracious 
creatures must be immense, and necessity may partly 
account for the greater boldness of the old birds at that 
season. By counting the nests from which the cry 
proceeds the condition of the rookery is ascertained, 
and the amount of sport it will afford reckoned with 
some certainty. By noting the nests from which the 
cry arose last, it is known which trees to avoid in the 
rook-shooting ; for the young do not all come to ma- 
turity at the same time, and there are generally a 
dozen or so which it is best to leave a week or a fort- 
night later than the rest. 
When the young birds begin to quit the nests, and 
