When the young sparrows were hatched, and feeding began, the wren suddenly became friendly. He hunted up small green worms, probably such as are good for wrenlings, and offered them to the young sparrows. Nestlings are never known to refuse anything to eat, and wren food seemed to suit the sparrows, for they soon outgrew the nursery. All summer this queer thing went on. The sparrows reared three or four broods, and the wren did his full share of the work,--and not only of feeding the young, but of repairing and rebuilding the nest for each fresh brood. XX HIS INTELLIGENCE BEFORE people knew very much about the ways of birds, it was thought that they did not have to be taught anything, but that they knew everything they needed to know, as soon as they were born. That is, they were said to act from instinct alone, and not at all from reason, as we do. Another notion that people had was that birds of a kind were just alike; that they looked exactly like each other, all acted in the same way, and all sang the same song. But since we have begun to study birds more closely, we find these things are not true. We find that birds learn things by being taught, as we do. Also, they find out how to do things themselves, and they are not all alike, as so many machines. More than this, we see that they do not look nor act exactly like each other. For when we know one robin or one oriole well, we can tell him from any other robin or oriole. And, as I said before, no two of a kind sing precisely the same song. A bird shows his intelligence in many ways. One is by the way he acts when he cannot do as he is used to doing. A robin I know of wished to build a nest, but could not find mud to put into it, for it was a very dry time, and there were no streams near. Now a robin's nest must have mud, and the bird seemed puzzled for a while. But at last she thought of a way to get it. She went to a bathing-dish that the people of the house kept filled with water for the birds, jumped into it, and got her legs very wet. Then she flew to the road, and tramped around in the dust and dirt. In a short time her legs had a good coating of mud, which she carefully picked off with her bill, and took to the nest she was building. This she did a great many times, and the lady who told me of it watched her till she had as much mud as she needed. A bird often shows sense by the way she repairs a nest that has been thrown out of place. Sometimes she will add a new stay, tying the nest to a stronger limb. One sparrow, whose nest broke loose, put so many stays to the branch above that they made a little roof like a tent over it.