WIND-RAPIDS ON THE HEIGHTS 79 



turned aside from the trail to see the behaviour of 

 the tallest woods, a dense growth of Engelmann 

 spruce, at the bottom of the steep slope of Battle 

 Mountain. 



I climbed into a tree-top one hundred feet high. 

 Around me the tall and crowded trees were sway- 

 ing and bowing through a dignified dance. In- 

 visible wind breakers produced sudden dips and 

 vigorous sweeps that my old tree thought he en- 

 joyed. Occasionally the tree-top swayed in one 

 direction, then bowed in another. Once he nodded 

 in succession toward all points of the com; 

 tracing a wavy circle perhaps twenty feet in diame- 

 ter. Then he straightened up again to the per- 

 pendicular. The entire forest was suddenly tilted 

 forward by a violent wind wave and without the 

 least warning I was clinging to a leaning tower. 

 Engelmann spruce wood is not celebrated for 

 toughness so I quickly descended to earth. 



In the shelter of the storm-battered trees at 

 timberline I looked out into the yellow, sand- 

 filled air upon a treeless Arctic moorland. The 

 gale tore among the trees with ever-varying in- 

 tensity. Sand and gravel pattered and rattled 

 against the scarred and veteran pines. I climbed 

 a low, stocky tree which the hardest wind waves 

 struck. This tree was so rigid that it quivered 

 and oscillated like a building in an earthquake. 



At the altitude of 11,500 feet I emerged from 

 the woods and faced the gale. It assailed me with 



