Jack was an attentive observer of all these proceedings, and he was greatly delighted to find that the wrens were willing to accept of the box in exchange for the cap. The next day, they began to build their nest in the box. It was very pleasant, indeed, to see the little creatures at work. They would carry up quite large sticks, and were very handy in getting them into the hole. They began their work by sunrise, and so industrious were they, that, in four days, the nest was finished. The lower part consisted of rough sticks and coarse straws. The upper part was finer, and the nest was lined with fine grass. In a week, there were four little spotted eggs in the nest. The female wren was now rather quiet, but the male wren was very watchful indeed. If he saw the cat coming near the trellis, he would fly at her, and snap his little beak close to her ears. Puss would sometimes strike her paws at him, but, in general, she was frightened and ran away. The little wren was very pugnacious. If a robin or a blue jay came near, he went at him in the most fearless way, and drove him off. One day, as Jack was watching him, the little fellow attacked a crow that was passing by, and, overtaking him, picked at him so sharply as to make the old fellow cry for quarter in a very loud voice. “Caw, caw, caw,” said the crow, and Mr. Wren, seeming satisfied, returned to his box. Perching himself upon the very top of the trellis, he began to sing a song of triumph, shaking his wings all the time, in great glee. The female wren soon began to sit upon the eggs, and nothing could exceed the watchful care and anxiety of good master Wren. He was always on hand, if any cat or bird intruded upon his dominions; and they were sure to pay dearly for their temerity when they did so. He spent a good deal of his time in singing, in part, I suppose, to amuse himself, and in part also to amuse his little lady. Well, after a time, there were four young birds in the nest, and both Mr. and Mrs. Wren were too busy in feeding their children, to sing or play. They caught flies, and moths, and spiders, and gave them to their young ones, and it was amazing to see what a sight of these insects the little wrens ate, and it was really amusing to see how serious the old wrens appeared to be about these days. The little ones grew apace, and in a short time it was thought best for them to leave the nest. You may well believe that Jack was on the look-out, to see the little creatures in their first adventure forth into the world. In the first place, one of the young birds put his head through the door of the box, and looked all round to see if the coast was clear. It was amazing to see how cunning the little fellow was, though not more than a fortnight old. The old wrens were at a little distance, chattering at a great rate, and seeming to invite the little fellow to try his wing. At last, he took courage, leaped from the box, and alighted safely upon a fence at some distance.