Geyser

Geyser (Icelandic geysir = "gusher"), denoting a fountain of steam and hot water discharged from holes in the ground in various countries, such as Iceland, North America, and New Zealand. The water may be clear and pure, or thick and muddy. The minerals held in solution may be sodium and potassium chlorides, calcium and sodium sulphates, various carbonates and silicates, etc. Such of these substances as separate by evaporations form a crater of solid matter around the orifice. The most wonderful are those near the Yellowstone river. One of these throws up at hourly intervals a column of water 6 feet in diameter to a height of 150 feet. The Icelandic geysers near Mount Hekla have been known since the 12th century. The pink terraces formed by the New Zealand geysers were famous for their beauty, but were destroyed in 1886 by volcanic eruptions. The phenomenon of geysers is associated with that of volcanoes. The eruptions are probably due to the intense heating of water far down in the funnel-shaped hole; the water cannot evaporate on account of the great pressure of the water above it that is at a temperature below boiling-point; but when, at more or less regular intervals, this superincumbent liquid is raised to the boiling-point by bubbles of steam that rise from below, it evaporates and causes the deeper liquid to boil with explosive violence.