Presently his mate appeared, and with a sharp note he called her down beside him.  Then both birds hopped and twittered about the rail, with apparently never a care in the world.  The male especially seemed just in the mood for a frolic.  He ran up and down the mossy rail; he whirled about it till he looked like a little gray pinwheel; he hung head down by his toes, dropped, and turned like a cat, so as to light on his feet on the rail below.  While watching his performance, I hardly noticed that his mate had gone till she reappeared suddenly on the rail beside him.  Then he disappeared, while she kept up the performance on the rail, with more of a twitter, perhaps, and less of gymnastics.  In a few moments both birds were together again and flew into the pines out of sight.

[Illustration]

I had almost forgotten them in watching other birds, when they reappeared on the rail, ten or fifteen minutes later, and went through a very similar performance.  This was unusual, certainly; and I sat very quiet, very much interested, though a bit puzzled, and a bit disappointed that they had not gone to their nest.  They had some material in their beaks both times when they appeared on the rail, and were now probably off hunting for more—­for rabbit fur, perhaps, in the old orchard.  But what had they done with it?  “Perhaps,” I thought, “they dropped it to deceive me.”  Chickadee does that sometimes.  “But why did one bird stay on the rail?  Perhaps”—­Well, I would look and see.

I left my stump as the idea struck me, and began to examine the posts of the old fence very carefully.  Chickadee’s nest was there somewhere.  In the second post on the left I found it, a tiny knot-hole, which Chickadee had hollowed out deep and lined with rabbit fur.  It was well hidden by the vines that almost covered the old post, and gray moss grew all about the entrance.  A prettier nest I never found.

I went back to my stump and sat down where I could just see the dark little hole that led to the nest.  No other birds interested me now till the chickadees came back.  They were soon there, hopping about on the rail as before, with just a wee note of surprise in their soft twitter that I had changed my position.  This time I was not to be deceived by a gymnastic performance, however interesting.  I kept my eyes fastened on the nest.  The male was undoubtedly going through with his most difficult feats, and doing his best to engage my attention, when I saw his mate glide suddenly from behind the post and disappear into her doorway.  I could hardly be sure it was a bird.  It seemed rather as if the wind had stirred a little bundle of gray moss.  Had she moved slowly I might not have seen her, so closely did her soft gray cloak blend with the weather-beaten wood and the moss.

In a few moments she reappeared, waited a moment with her tiny head just peeking out of the knot-hole, flashed round the post out of sight, and when I saw her again it was as she reappeared suddenly beside the male.