down to the Firehole River; and thus "Old Faithful" keeps it up regularly every hour. The eruption being ended, you can look down into the abyss whence it came. Through the hot steam, rushing out with a strong draught, there is a view far down into the rocky recesses of the geyser. The water left by the eruption stands about in transparent shallow pools, and is tinted a pale blue. "Old Faithful's" mound is built up of layers of geyserite--hard, brittle, porous, full of crevices, and having all about little basins with turned-up rims that retain the water. This geyser is the favorite in the region, not only because of its regular performance, but possibly because its odors are somewhat less sulphurous than those emanating elsewhere. The geysers of the Upper Basin contribute practically the whole current of the Firehole River, their outflow sending into the stream ten million gallons daily. Across the river to the northward, close to the bank, is the Beehive, its tube looking like a huge bird's nest, enclosed by a pile of geyserite resembling a beehive, three feet high and about four feet in diameter. Nearby is a vent from which steam, escaping a few minutes before the eruption, gives notice of its coming. The water column shoots up two hundred feet, with clouds of steam, but it is quite uncertain, spouting once or twice in twenty-four hours, and usually at night. Behind the Beehive are the Lion, the Lioness, and their two Cubs, and to the eastward of the latter the Giantess. The Lion group has only uncertain and small action, while the Giantess is on the summit of a mound fifty feet high, with a depressed crater, measuring eighteen by twenty-four feet, and usually filled with dark-blue water. This is the slowest of all the geysers in getting to work, acting only at fortnightly intervals, but each eruption continues the greater part of the day, with usually long-previous notice by violent boiling and internal rumblings. When it comes, the explosion is terrific, the column mounting two hundred and fifty feet, a perfect water-spout the full size of the crater, with a half-dozen distinct jets forced through it. To the northwest of the Lion and across the river is the Castle, so named from the castellated construction of its crater. It stands upon an elevation, the side towards the Firehole falling off in a series of rude steps. The tube is elevated about ten feet within the castle and is four feet in diameter. It is of uncertain eruption, sometimes playing daily and sometimes every other day, throwing a column of one hundred and fifty feet, falling in a sparkling shower, continuing about forty minutes, and then tapering off in a series of insignificant spurts. The Saw-Mill is not far away, rather insignificant, its tube being only six inches in diameter, set in a saucer-like crater about twenty feet across; but its water column, thrown forty feet high, gives the peculiar sounds of a saw, caused by the action of puffs of steam