290 CAPRIMULGID^. 



wheel in rapid revolution.* It is nearly monotonous but 

 not quite so, as it occasionally rises or falls about a quarter 

 of a note, and appears to increase and diminish in loudness. 

 iSTor does it seem to proceed continuously from exactly the 

 same spot, but to vary its position, as if the performer were 

 either a ventriloquist or were actually shifting his ground. 

 Fortunate observers have been able to creep up close enough 

 to make out that the bird perches with its feet resting 

 lengthwise on a branch, its claws not being adapted for 

 grasping, and turns its head from side to side, thus throw- 

 ing the sound as it were in various directions, and pro- 

 ducing the same effect as if it proceeded from different 

 places. I have repeatedly worked my way close up to the 

 bird, but as I labour under the disadvantage of being short- 

 sighted, and derive little assistance from glasses at night, I 

 have always failed to observe it actually perched and sing- 

 ing. In the summer of 1859 a Nightjar frequented the 

 immediate neighbourhood of my ow^n house, and I had 

 many opportunities of listening to its note. One evening 

 especially, it perched on a railing within fifty yards of the 

 house, and I made sure of seeing it, but when I had 

 approached within a few yards of the spot from whence 

 the sound proceeded the humming suddenly stopped, but 

 was presently again audible at the other end of the railing 

 which ran across my meadow. I cautiously crept on, but 

 with no better success than before. As I drew near, the 

 bird quitted its perch, flew round me, coming wdthin a few 

 feet of my person, and, on my remaining still, made itself 

 heard from another part of the railing only a few yards 

 behind me. Again and again I dodged it, but always with 

 the same result ; I saw it, indeed, several times, but always 

 on the wing. At last a longer interval of silence ensued, 

 and when I heard the sound again it proceeded from a 



* Mr. Bell informs me that it is so like the croak of the Natter- 

 Jack Toad, tbat he has more than once doubted from which of the 

 two the sound proceeded. 



