406 The Griffon Vulture 
20 to 25 ft. above the ground. I know of some quiet valleys where, 
if a strong wind be blowing, I am sure of seeing over thirty 
Vultures thus at rest, especially after three o'clock of an afternoon, 
which seems to be the hour when they usually discontinue their 
marvellous aerial reconnaissances in quest of carrion. 
