When his mate appeared the merry birds would chase off for a race through the treetops. Song and play were mingled with their work, but, for all that, the happy builders' house grew under their hands, and they kept faithfully at their task of preparing the home for their little brood. Once the small, dainty mother bird,—surely it must have been she,—after putting in her bit of moss, settled down in the nest and sat there the picture of quiet happiness.

This was all I saw of the nest builders that year. A great storm swept through the valley, and it must have washed away the frail mossy cup, for it was gone and the tree was deserted. Nevertheless, the birds had been so attractive, and their nest so interesting, that through the five years that passed before my return to California I kept their memory green, and could never think of them without tenderness—though I could call them by no name. If they had only worn red feathers in their caps, it would have been some clue to their coats-of-arms; but, out of hand, there seemed to be nothing to mark the plain, little, greenish gray birds from half a dozen of their cousins.

When I finally returned to the California ranch, one of my first thoughts was for the moss nest makers up in the oaks. Now I had a chance to solve the mystery without harming one of their pretty feathers, for by long and patient watching I might get near enough to puzzle out the 'spurious primary' and the subtle distinctions of tint that make such a difference in calling birds by their right names.

For six weeks I watched and listened in vain, but one day when riding up the canyon rejoicing at the new life that filled the trees, I stopped under an oak only a few rods from the one where the nest had been five years before, and looking up saw a small dull-colored bird with a bit of moss in its bill walking down into a mossy cup right before my eyes! For a few moments I was the happiest observer in the land. I had found my little friend again, after all these years! It looked over the edge of the twig at me several times, but went on gathering material as unconcernedly as if it, too, remembered me. The mossy cup seemed prettier than any rare bit of Sèvres china, for I looked upon it with eyes that had been waiting for the sight for five years.

As the bird worked, a cottontail rabbit rustled the leaves, and Billy started forward, frightening the timid animal so that it scampered off over the ground, showing the white underside of its tail. But though Billy and the rabbit were both terrified, the brave worker only flew down to a twig to look at them, and turned back calmly to its task.

The nest was so protectively colored that I could not see it readily, and sometimes started to find that I had been looking right at it without knowing it. The prospect of identifying my birds was not encouraging. You might as well expect to see from the first floor what was going on up in a cupola as to expect to see from the ground what birds are doing up in the thick oak tops. You have reason to be thankful for even a glimpse of a bird in the heavy foliage, and as for 'spurious primaries,'—"Woe worth the chase!"

Now and then I got a hint of family matters. My two little friends were working together, and occasionally I saw a bit of moss put in; but it was evident that the main part of the work was over. One day I waited half an hour, and when the bird came it acted as if it had really done all that was necessary, and only returned for the sake of being about its pretty home.

The birds said a good deal up in the oak, sometimes in sweet lisping tones, as though talking to themselves about the nest. They often flew away from it not far over my head. The call note was a loud whistle—whee-it'—and the bird gave it so rapidly that I once took out my watch to time him, after which he called seventy times in sixty seconds. Often after whistling loudly he would give a soft low call. His clear ringing voice was one of the most cheering in the valley.

When the building seemed done and I was looking forward to the brooding, as the birds would then, perforce, be more about the nest, one sad morning I rode up through the oaks and found the beautiful moss cup torn and dangling from its branch. It was the keenest disappointment of the nesting season, and there had been many. The pretty acquaintance to whose renewal I had looked forward so many years was now ended.

Again I had to leave California without being able to name my winning little friends. If I had been too much interested in them before to set a price on their heads; now, rather than raise my voice against them, they should remain forever unnamed.[4]