Fountains which from time to time, under the expansion of steam, eject columns of steam and hot water, and which are met with in Iceland, North America, and New Zealand, of which the most remarkable is the Great Geyser, 70 m. N. of Reikiavik, in Iceland, which ejects a column of water to 60 ft. in height, accompanied with rumblings underground; these eruptions will continue some 15 minutes, and they recur every few hours.