on some Swiss Birds. 147 



flying round the tovrer, uttering their harsh scream ; we 

 then went up the tower and questioned the custodian, who 

 told us that all the birds were now sitting, and that most 

 probably the young were hatched, but that we could go 

 and see for ourselves. We then went higher still to see the 

 nests, the floor being very dirty, owing to the mutings of 

 the birds, to say nothing of the dust ; it was also very dark, 

 there being no light except from under the roof. The nests, 

 of which we could see about twenty, were placed on the ledge 

 which goes round the tower, and about 4 feet below the main 

 floor, on which we were standing, so we were obliged to 

 kneel down and look very quietly over the edge at the nests ; 

 sometimes there were three or four in the space of 3 yards, all 

 placed on the same beam, and on most of the nests which we 

 could see there was an old bird sitting. On making the 

 least noise, the sitting birds would immediately look up at 

 us, and then roll themselves off the nests, disappearing with 

 harsh screams into the air, but would soon come flying back 

 again under the roof and crawl to their nests. 



The male and the female appear to take turns in sitting on 

 the eggs, for as we were watching a bird on its nest, another 

 Swift suddenly dashed in under the roof and began to caress 

 the bird on the nest ; they both kept twisting their heads 

 about, rubbing against each other's cheeks with open bills; 

 then the sitting bird rolled itself off' the nest and vanished 

 into space, the other taking its place. 



We were lucky in finding one nest which still contained 

 two freshly laid eggs, which we took ; other nests contained 

 eggs already much incubated, and one had young just hatched, 

 with only a little black down on them. The nest is very 

 shallow, constructed of dry leaves, bits of paper, a few dry 

 grass-stems, bits of fir-bark, and a few feathers, the whole 

 being made fairly solid by the mucous fluid which the bird 

 emits. The nest was infested by a parasite. The eggs, 

 generally four in number, are pure white, and out of 35 eggs 

 we obtained no varieties in colour, but some are much larger 

 than others. 



The Alpine Swift nests in colonies in many of the cathedral 



l2 



