During eruptions large volumes of carbon dioxid and some hydrogen sulfid and a little free hydrogen are emitted. In 1909 my maximum recording thermometer was lowered to a depth of eighty feet and the temperature was 110C., or 230 degrees on the Fahrenheit scale. Words convey but a meager idea of the magnificence of this geyser during eruption, or the awe with which it inspires the witness of its extraordinary display of power. It was six-thirty in the evening, eight hours after we had administered the emetic of soap. Not a cloud dimmed the blueness of the sky and no air was stirring. The glaciers of _Láng Jökull_, the long ice-covered mountain, loomed beyond the plain of the _Hvitá_, White-River, the dome of _Hekla_, Hooded, had momentarily lost its cloud mantle, all the little geysers and fumaroles were boiling merrily and steaming furiously. Even quiet _Blesi_ was sending up showers of carbon dioxid bubbles. The signs were favorable for an exhibition and the people were gathered close about the Inn in expectation. What the condition of the air has to do with the eruption, I do not suggest. Icelanders familiar with _Geysir_ state that “when the wind is from the north there is never an eruption.” I can only add that during our first eighteen hours at this place we had a strong wind from the north and no eruption. We were at supper. The ground trembled, the building vibrated and a dull rumbling reached the ears. “_Geysir! Geysir!_” rose the cry from within and without the building. The supper was never finished. Johannes, who had been watching for these first signs ever since we had administered the emetic, met us as we sprang to the doorway. Everyone rushed to the elevation across from _Geysir’s_ runway. Again the rumble, heavier than before. The water is agitated in the basin, it boils up suddenly, subsides, the earth beneath our feet trembles and a mass of steaming water rises in the center of the basin to an elevation of fifteen feet and overflows the rim with a noisy splash. Then all is quiet. Is this what we had travelled forty miles out of our way to see? Truly a great fuss for nothing. Is this the wonderful _Geysir_ whose manifestation of power had caused the devout Henderson to fall upon his knees and to pour out his “soul in solemn adoration of the Almighty Author of nature, ‘who looketh on the earth, and it trembled; who toucheth the hills, and they smoke?’” Does _Geysir_ demand more tribute in soap? A few moments of quiet expectation followed. Then, without further warning, a column of superheated water, ten feet in diameter, shot like a rocket into the air to the height of one hundred and twenty-five feet and the abysmal forces maintained that column for nine minutes. What a flood of water poured down the sloping cone! What a fountain! Mark Twain said that they “have real fountains in Europe but in America they only leak.” What would he have said could he have