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THE WORLD. 



that the rushing of the waters may be heard as they flow in their 

 subterranean channels. ' The springs are intermittent, a fountain 

 of boiling water accompanied with a great evolution of vapor, 

 first appears, and is ejected to a considerable height, sometimes 

 as much as one hundred feet, a volume of steam succeeds, and 

 is thrown up with great force and a loud noise, similar to the es- 

 cape of steam from the boiler of an engine. This operation con- 

 tinues sometimes for more than an hour, though generally not 

 longer than ten minutes, and is succeeded by a period of rest of 

 uncertain duration, and then a repetition of the same phenomena. 

 We give a view of the crater of the great Geyser reduced by Mr. 

 Lyell, from a sketch by J. W. Hooker, M. D. The basin of the 

 great Geyser is an irregular oval about fifty-six feet, by forty-six, 

 the silicious mound of which it is formed, is about seven feet 

 high. In the centre is a pipe s'eventy-eight feet in perpendicular 

 depth, and about sixteen feet diameter at the top, but contracting 

 to ten feet lower down. The circular basin is represented as 



empty, but it is usually filled with a beautifully transparent water 

 in a state of ebullition ; the inside of the basin is smooth and 

 formed of a whitish silicions deposit, as are also two channels at 



