196 THE MIGRATION OF HIRUNDO RUSTICA. 



a single great cloud. Wherever we look the swarms are 

 fast approaching; the grand sight of the confluence of two 

 multitudes of birds just witnessed repeats itself on all sides. 

 Quicker, dear reader, than I am able to express to you in 

 words, most of these living clouds, at times overshot with 

 a gleam of reddish sheen, the reflection of some real clouds 

 still beaming in crimson on the far western horizon, have 

 united in ten large swarms — no, in eight only ; and look, 

 they are still uniting ! Our cries cease ; we remain silent for 

 a few moments, and then a loud cheer rings through the air. 

 The endless swarms of Swallows have united into a single 

 mighty cloud. Who could count them ? The air is filled 

 with them and with the noise they make with wings and 

 voices. The swarm of more than hundreds of thousands 

 moves up and down, to and fro, lowering itself quickly down 

 to the reeds and rising just as swiftly high up into the air ; 

 it moves like a living tidal wave and sounds like the rushing of 

 mighty winds. And the voice of those countless feathered 

 singers expresses their pleasure at having met again at the 

 place of their night's rest, which they have visited for weeks 

 already and to which they will nightly resort for four months 

 longer before departing for the far north. 



The faded crimson on the western sky has disappeared. 

 The evenings on these high African plateaus are very short. 

 The night is fast approaching. Still the living, dark and 

 noisy billow rolls up and down, a little less voluminous than 

 before, as thousands have already joined the whistling 

 Finches among the reeds. Suddenly the wave subsides, and 

 turns sharply toward the grassy plain, as if it would leave the 

 swamp for good ; but just as suddenly it returns in a semi- 

 circle and striking the reeds sinks among them, not to 

 rise again. The voices still keep on ; no wonder that dis- 

 putes arise among the Swallows themselves and also with 

 the Finches regarding about three inches of space on the same 

 reed stem. This noise keeps on for about a quarter of an hour^ 

 when it ceases. At last the weary birds have found a place 



