We lay on the turf covering a ledge of smoky quartz thrust like a wedge into the marsh. Across a country of round green hills and fertile farms its squat bulk stretched unafraid, an untamed monster of another age. Beyond the long levels we could see Wolf Island, where a hunted wolf-pack, protected by quagmires and trembling bogs, made its last stand two centuries ago. Where a fringe of trees showed the beginning of solid ground, a pair of hawks with long black-barred tails wheeled and screamed through the sky. "Geck, geck, geck, geck," they called, almost like a flicker, except that the tone was flatter. As they circled, both of them showed a snowy patch over the rump, the field-mark of the marsh hawk. The male was a magnificent blue-gray bird, whose white under-wings were tipped with black like those of a herring gull. We watched them delightedly, for the rare nest of the marsh hawk, the only one of our hawks which nests on the ground, was one of the possibilities of the marsh. Suddenly we heard from behind us a sound that sent us crawling carefully up to the crest of the ridge. It was like the pouring of water out of some gigantic bottle or the gurgling suck of an old-fashioned pump: "Bloop--bloop, bloop, bloop, bloop"--it came to us with a strange subterranean timbre. The last time I had heard that note was in the pine-barrens three years before. Then it sounded like the thudding of a mallet on a stake, for its quality always depends on the nature of the country across which it travels. From the top of our knoll we saw a rare sight. In the open pasture by the edge of the marsh stood a bird between two and three feet high, of a streaked brown color, with a black stripe down each side of its neck. Even as we watched, the bird began a series of extraordinary actions. Hunching its long neck far down between its shoulders, it suddenly thrust it up. As each section straightened, there came to us across the pasture the thudding, bubbling, watery note which we had first heard. It seemed impossible that a bird could make such a volume of sound. At times, after each "bloop," would come the sharp click of the bill as it rapidly opened and shut. Finally the singer convulsively straightened the last kink out of its neck and with a last retching note thrust its long yellow beak straight skyward. We had seen an American bittern boom--a rarer sight even than the drumming of a ruffed grouse or the strange flight-song of the woodcock at twilight. Suddenly the bittern stopped and, hunching its neck, stepped stealthily, like a little old bent man, into the sedges. With its long beak pointing directly upward, it stood motionless and seemed to melt into the color of the withered rushes. One look away, and it was almost impossible for the eye to pick the bird out from its cover.