Higher and higher I climbed, the mountain side being so steep that my breath came in gasps, and I was often compelled to throw myself on the ground to recover strength. At length a bird darted out from the pines several hundred feet above me, rose high into the air, circled and swung this way and that for a long time, breaking at intervals into a song which sifted down to me faintly through the blue distance. How long it remained on the wing I do not know, but it was too long for my eyes to endure the strain of watching it. Through my glass a large part of the wings showed white or yellowish-white, and seemed to be almost translucent in the blaze of the sunlight. What could this wonderful haunter of the sky be? It was scarcely possible that so roly-poly a bird as a grosbeak could perform so marvellous an exploit on the wing. I never worked harder to earn my salary than I did to climb that steep and rugged mountain side; but at last I reached and penetrated the zone of pines, and finally, in an area covered with dead timber, standing and fallen, two feathered strangers sprang in sight, now flitting among the lower branches and now sweeping to the ground. They were not grosbeaks, that was sure; their bills were quite slender, their bodies lithe and graceful, and their tails of well-proportioned length. Save in color, they presented a decidedly thrush-like appearance, and their manners were also thrush-like. Indeed, the colors and markings puzzled me not a little. The upper parts were brownish-gray of various shades, the wings and tail for the most part dusky, the wing-coverts, tertials, and some of the quills bordered and tipped with white, also the tail. The white of both wings and tail became quite conspicuous when they were spread. This was the feathered conundrum that flitted about before me. The birds were about the size of the hermit thrushes, but lither and suppler. They ambled about gracefully, and did not seem to be very shy, and presently one of them broke into a song--the song that I had previously heard, only it was loud and ringing and well articulated, now that I was near the singer. Again and again they lifted their rich voices in song. When they wandered a little distance from each other, they called in affectionate tones, giving their "All's well."