After an hour's observation near to the volcano I retired some fifty feet, and, sheltering myself under a stunted pine, waited in the hope of seeing a greater outbreak. After an hour more the boiling lessened and the frequent explosions ceased for perhaps fifteen minutes. Then of a sudden came a booming sound, followed by a hoarse noise, as the crater filled with steam, out of which shot, some seventy-five feet in air, about a cartload of mud. It fell over an area of fifty yards around the crater in large or small masses, which flattened as they struck. As soon as it ended I walked toward the crater. A moment later a second squirt shot out sideways and fell in a line athwart the mud-pool near by, crossing the spot where I had been standing so long, and covering me, as I advanced, with rare patches of hot mud. Some change took place after this in the character and consistency of the mud, and now, at intervals, the curious spectacle was afforded of rings of mud like the smoke-rings cast by a cannon or engine-chimney. As they turned in air they resembled at times the figure 8: once they assumed the form of a huge irregular spiral some ten feet high, although usually the figures were like long spikes, or, more rarely, thin formless leaves, and even like bats or deformed birds. I walked back over the hills to camp, where we found Captain G. and the commissary with the best of two deer they had shot. Later, Mr. C. and Mr. K. came in with four elk, so that we were well supplied. Of these various meats the deer proved the best, the mountain-sheep the poorest. The minimum of the night temperature was 34 deg. Fahrenheit. At eighty-five hundred feet above tide the change at sundown was abrupt. Our camp-fires had filled the little valley with smoke, and through it the moon rose red and sombre above the pine-clad outlines of the eastward hills. The next day Mr. E. and I, who liked to break the journey by a walk, started early, and, following a clear trail, soon passed the mules. We left Pelican Creek on our right, and crossed a low divide into a cooly,[B] the valley of Broad Creek: a second divide separated this from Canyon Creek, both of which enter the Yellowstone below the falls. After some six miles afoot over grassy rolling plains and bits of wood, the command overtook us, and, mounting, we followed the major for an hour or two through bogs and streams, where now and then down went a horse and over went a trooper, or some one or two held back at a nasty crossing until the major smiled a little viciously, when the unlucky ones plunged in and got through or not as might chance.