Northern Observations of Inland Birds 67 



we have it again in the smack system of the beaver and 

 musquash, which, by striking the water with their tails, 

 spread the news of danger far and wide, and those working 

 under water are prevented from rising haphazard. But, in 

 the case of the nightjar, the signal is not an alarm signal, 

 for fear seems to be unknown to this child of the twilight. 

 It simply conveys the intelligence and the enquiry : 

 *' Here am I. Where are you ? " 



My observations of the nightjar have repeatedly gone 

 to support this belief. True, I have often heard these 

 birds flapping their wings above their backs without 

 answer, but again, especially immediately succeeding 

 their arrival here — that is when the mating instinct is at 

 its height — I have heard them unquestionably call and 

 answer each other by this flapping means of telegraphy. 



One particular instance sticks in my mind. It was on 

 the River Wharfe, and after midnight, when, from sheer 

 fatigue, I left the trout still rising freely and made my 

 way across the meadows towards the white-walled home- 

 stead standing under its chestnut trees. On the way I 

 heard two nighthawks flapping to each other, now fifty 

 yards, now three hundred, now four meadows apart. 

 One would flap twice, and immediately two flaps would 

 come in answer. There would be a pause, then four rapid 

 flaps, surprisingly near my head, and faint and far from 

 the distance the answer would come. Generally, but 

 not always, the signal was answered in the same number 

 of strokes as it was given ; in the higher numbers six 

 might answer four, or five might answer three, but it 

 was clear to anyone listening that the birds were carrying 

 on a primitive form of Morse telegraphy. And this is 

 but one incident out of many I have observed when the 

 flapping of the nightjar, casually remarked upon by so 

 many naturalists, has struck me as being used by a courting 

 couple as a means of keeping in touch with one another. 



E 2 



