12:30
Now the mental and physical equipments of the last lot of young birds were to be put to test . Although there were plenty of witnesses , I thought it best to close all but one of the pigeon-doors and stand ready to shut that behind the first arrival . I shall never forget the sensations of that day . I had been warned : `` They start at 12 ; they should be here at 12:30 ; but look out , they come like a whirlwind . You hardly see them till they 're in . '' We were ranged along the inside of the loft , each with an eye to a crack or a partly closed pigeon-door , anxiously scanning the southwestern horizon , when one shouted : `` Look out -- here they come ! '' Like a white cloud they burst into view , low skimming over the city roofs , around a great chimney pile , and in two seconds after first being seen they were back .