92 BIRD LIFE IN A WESTERN VALLEY 



I waited on till the other bird became alarmed 

 at a stone thab I inadvertently loosened, and 

 with a loud chit-chit sped down-stream out of 

 sight. Then, swinging from tree-trunk fco tree- 

 trunk, I descended to the bottom of the gorge, 

 walked towards the crag, and quickly discovered 

 the exact position of the dippers' nest. By the 

 oak-tree's root hung a fringe of long, withered 

 grass, and a thick cluster of polypody ferns 

 drooped over the grey, lichen-covered base of 

 the crag. Dead leaves, that had lingered through 

 the winter on the oaks, and had at length been 

 pushed away by the swelling buds, were strewn 

 alike on grass and fern. Beneath the polypody 

 roots, from the long filaments of which the rain 

 had washed the soil, a number of leaves appeared 

 to have been collected by chance while falling 

 from the oak ; but this seemingly haphazard 

 collection really formed a ball-shaped structure 

 the snug, well-roofed sanctuary that my little 

 friends had built with care and perseverance. 



To approach the nest by climbing down the 

 crag was impossible ; the bluff towered perpen- 

 dicularly for more than a hundred feet above the 

 oak, and afforded not the slightest foothold. So, 

 taking off some of my clothes, I waded into the 

 ice-cold stream, which here spread out into a 

 pool about three feet deep and five yards broad. 

 When I had gone half-way across, the dipper 



