By J. ALLISON ATWOOD WHY BIRDS MIGRATE There are very few people who really know why birds migrate--that is, fly south in the fall, and then return to us in the springtime. Some say that they cannot stand the cold, and so escape it by going south where it is warm all winter. Others believe that at the end of summer the birds have eaten all their food, so they have to go to some locality where the insects and other dainties have not all been devoured. Both of these explanations seem reasonable until one has learned the real cause. A great many years ago, hundreds and hundreds in fact, birds stayed all year round in the same place they had built their nests, and, no doubt, they would do so now if they had their choice. But as it is, they no sooner feel the first breath of winter than they hurry away as if pursued by some enemy. And that they have some reason to fear, I’m sure you will agree when you have heard it. It was a very cold winter. Most of the birds had to move out of their summer homes. Brown-thrasher and Song-sparrow had been forced to give up their thickets, all the undergrowth being dead. Thereupon the former grumbled much because Flicker was so well sheltered from the cold. In the summer time, Thrasher had been among the first to make fun of the carpenter for building such a peculiar house, but now he looked longingly at him as he disappeared within the comfortable-looking hollow limb. Kingfisher, too, was regarded with more respect as he took shelter in the long tunnel which he had made during the previous summer. But as for those most unfortunate birds who had built on the ground, as Bobolink and Meadowlark, they, indeed, were very much put out, for their houses were entirely covered with snow. Still, it is very probable that everyone would have stayed north all winter had not something far more dreadful occurred.