Here about the farm, this is sure to be a gray birch home. Other trees will do—on a pinch. I have found chickadee nesting in live white oaks, maples, upturned roots, and tumbling fence posts. These were shifts, however, mere houses, not real homes. The only good homelike trees are old gray birches dead these many years and gone to punk,—mere shells of tough circular bark walls. Why has chickadee this very decided preference? Is it a case of protective coloration,—the little gray and black bird choosing to nest in this little gray and black tree because bird and tree so exactly match each other in size and color? Or (and there are many instances in nature) is there a subtle strain of poetry in chickadee’s soul, something æsthetic, that leads him into this exquisite harmony,—into this little gray house for his little gray self? Explain it as you may, it is a fact that this little bird shows a marked preference, makes deliberate choice, and in his choice is protection, and poetry, too. Doubtless he follows the guidance of a sure and watchful instinct (whatever instinct be), but who shall deny to him a share of the higher, finer things of the imagination? a share of real æsthetic taste? His life inside the birch is of a piece with the artistic exterior. It is all gentle and sweet and idyllic. There is no happier spot in the summer woods than that about the birch of the chickadees; and none whose happiness you will be so little liable to disturb. Before the woods were in leaf one spring I found a pair of chickadees building in a birch along the edge of the swamp. They had just begun, having dug out only an inch of cavity. It was very interesting to discover them doing the work themselves, for usually they refit some abandoned chamber or adapt a ready-made hole. The birch was a long, limbless cylinder of bark, broken off about fourteen feet up, and utterly rotten, the mere skin of a tree stuffed with dust. I could push my finger into it at any point. It was so weak that every time the birds lighted upon the top the whole stub wobbled and reeled. Surely they were building their house upon the sand. Any creature without wings would have known that. Birds, however, seem to have lost the sense of such insecurity, often placing their nests as if they expected them also to take wings and fly to safety when the rains descend and the winds come. This shaking stub of the chickadees was standing directly beneath a great overshadowing pine, where, if no partridge bumped into it, if two squirrels did not scamper up it together, if the crows nesting overhead did not discover it, if no strong wind bore down upon it from the meadow side, it might totter out the nesting season. But it didn’t. The birds were leaving too much to luck. I knew it, and should have pushed their card house down, then and there, and saved the greater ruin later. Perhaps so, but I was too interested in their labor.