NIGHTHAWK 211 



stationarily for a moment, somewhat like a kingfisher, 

 and then dive almost perpendicularly downward with a 

 rush, for fifty feet, frequently within three or four rods 

 of us, and the loud booming sound or rip was made just 

 at the curve, as it ceased to fall, but whether volunta- 

 rily or involuntarily I know not. They appeared to be 

 diving for their insect prey. What eyes they must have 

 to be able to discern it beneath them against the rocks 

 in the twilight! As I was walking about the camp, one 

 flew low, within two feet of the surface, about me, and 

 lit on the rock within three rods of me, and uttered a 

 harsh note like c-o-w, c-o-w, — hard and gritty and al- 

 lied to their common notes, — which I thought expres- 

 sive of anxiety, or to alarm me, or for its mate. 



I suspect that their booming on a distant part of the 

 mountain was the sound which I heard the first night 

 which was like very distant thunder, or the fall of a 

 pile of lumber. 



They did not fly or boom when there was a cloud or 

 fog, and ceased pretty early in the night. They came 

 up from the same quarter — the shaded rocks below — 

 each night, two of them, and left off booming about 8 

 o'clock. Whether they then ceased hunting or withdrew 

 to another part of the mountain, I know not. Yet I heard 

 one the first night at 11.30 p. m., but, as it had been a 

 rainy day and did not clear up here till some time late 

 in the night, it may have been compelled to do its hunt- 

 ing then. They began to boom again at 4 a. m. (other 

 birds about 4.30) and ceased about 4.20. By their color 

 they are related to the gray rocks over which they flit 

 and circle. 



