When he gets his twig, he carries it to a dark, sooty chimney. A queer place for a home, surely. They used to choose a hollow tree or a cave to live in, and that seems much nicer. But chimneys are now more plentiful than hollow trees. And besides, they are nearer the bird's food. So chimney homes are now the fashion in the swift family. To make a swift nest, the twigs are glued to the chimney in the shape of a little bracket. The glue is the saliva of the bird, which is gummy, and gets hard as it dries, and looks like isinglass. The mouth of a chimney swift is very odd. You have heard of "stretching a mouth from ear to ear." That's just what the swift does every time he opens his. It needs to be big, for he gathers up his food in it. While he is flying around in the air, he is busy catching tiny flying creatures, such as flies and beetles, and thus keeping the air clear for us. The tail of this bird is another queer thing. It has no soft feathery tips like most birds' tails. It ends in sharp spines, like needles. These are most useful to brace him against the rough chimney where he sleeps. These spines are really the stiff shafts or stems of the feathers, sticking out beyond the plumey part. The chimney swift hangs himself up to sleep. He fastens his sharp claws into the rough bricks, and props himself firmly with his spiny tail. Even when the young swift is but two weeks old, he crawls out of the nest and hangs himself up under it. He seems to like that for a change from forever lying in a narrow bracket. Chimney swifts are social birds. They can't bear to be alone. They are almost always seen flying about in small parties, and calling to each other as they go, a strange, chattering cry. They are of a sooty color suitable to their sooty home, and the pair are alike. Vaux's swift is a little smaller and paler than the common chimney swift. The young swift is longer in his nursery than any bird of his size in the United States. He is four weeks old before he ventures out of his grimy home, though before that he will come up to the door to be fed. A late writer in a newspaper tells a little story showing the affection of a chimney swift for her little one. The writer had watched all summer a party of swifts who lived in one of his chimneys. A month or more after he supposed that all had flown away to the South beyond our southern boundary, where they spend the winter, he heard the twittering of one in the chimney. He took out the fireboard and found there a young bird. He was full grown and able to fly, but he was fastened by a horsehair to the nest. This had been pulled off by his weight, and lay on the hearth, holding him prisoner. The little fellow seemed to know he was to be helped, for he lay still while the man looked to see what was the matter. His mother soon came into the chimney with food. She took her place beside the man and waited, while he cut the strong hair and set the nestling free.