76 REPORT — 1855. 



tioned crag, are two tremendous holes or underground caverns, 30 or 40 feet deep, 

 filled and seething over with boiling water of the most perfect limpidity. These are 

 coated to their edge with a thin crust of earth or crumbly rock ; and although really 

 beautiful objects, such vast caldrons can scarcely be gazed into from so unsound a 

 margin without a certain feeling of awe. Several of the holes in the lower portion 

 of the field are of a similar description, being, in fact, irregularly shaped caverns, 

 quietly running over with boiling water, which to their bottom is as clear as crystal, 

 and of a fine light green hue. In one of them we observed large bubbles, probably 

 a foot in diameter, rapidly evolved, and rising in one direct line from some lower 

 region to another higher up, but which did not ascend to the surface ; nor could we 

 perceive that they had any direct communication with other orifices in the vicinity, 

 although undoubtedly some such existed. Some of the smaller holes bubble out 

 water with much noise, and six of these, we noticed, close to others perfectly limpid, 

 emitted boiling mud. 



The paramount objects, however, of this wonderful locality are the Geyser and 

 the two Strokrs, and to these we shall confine our remarks. 



The Geyser is the only one of the three which has formed a mound or siliceous 

 deposit round its orifice. From the sloping nature of the ground this mound ia 

 more than one-half higher on the east than it is on the west side, and extends three 

 or four times farther in the former than it does in the latter direction, attributable, 

 probably, to the greater prevalence of westerly winds in this locality. 



The western side may be 15 to 20 feet in height, the eastern can be little short of 

 25 or 30. The northern, the western, and the southern are comparatively abrupt, 

 while that on the east slopes away gradually ; but throughout, they form one mass 

 of siliceous deposit, which is roughened on the surface with what, at a little di- 

 stance, might be taken for an irregular circular flight of steps. The section of the 

 Geyser may be compared to a funnel, its pipe or orifice resembling the stalk, and its 

 cup or basin the head of that utensil. The cup is nearly round, its diameters 

 taken in opposite directions being 72'6 and 68*1 ; while its depth, measuring per- 

 pendicularly from a line drawn across its margin, appeared to be nearly 4 feet. The 

 pipe we ascertained to be 83"2 in depth, and rather more than 10 feet in diameter. 

 Under ordinary circumstances, when the Geyser is quiescent, this cup and pipe 

 are filled to the brim with limpid hot water, which ever and anon, but at totally 

 irregular periods, boils up in the centre, and then the water runs over, principally at 

 the points where the lip is a few inches lower than elsewhere in the circle. This is 

 a mere abortive attempt ; when, however, an eruption takes place, which almost 

 invariably is preceded by a premonitory subterranean rumbling noise, resembling the 

 looming of distant cannon, and by a trembling of the earth under foot, these ebullitions 

 rise higher, first in a mass of 2 or 3 feet, which opens in the centre, and surges 

 outwards like a wave, and then the water is suddenly ejected into the air, with the 

 velocity and din of some hundred sky-rockets, the entire mound being immediately 

 overflowed. This occurred four times during the thirty-six hours we were on the 

 spot, two of these eruptions being on the grandest and most brilliant scale ; which, 

 after waiting patiently for no less than twenty-seven hours, without the slightest 

 appearance of action, we were fortunate enough to witness, the first at half-past eleven 

 at night, the other at six the following morning. After an eruption, the water re- 

 cedes in the pipe, and not only is the cup left entirely dry, but 8 or 10 feet of 

 the pipe is likewise emptied. The inside of the pipe appears perfectly smooth, and 

 is nearly circular ; but the cup, or upper portion of the funnel, as well as the entire 

 mound outside of it, are both covered with siliceous incrustations, deposited by the 

 water, and doubtless still more by the volumes of steam or spray arising from it. 

 Inside of the cup, these incrustations present a smooth, dull ash-gray coloured crust, 

 dotted with occasional pure white concretions of extreme beauty. When broken up, 

 this crust yields an exceedingly hard sinter, bearing considerable resemblance in 

 colour, when cut and polished, to some varieties of madrepore. Outside the mound, 

 these incrustations assume the figure of cauliflower heads, and many other forms, 

 which, although deposited perfectly white, shortly become gray ; and which, not- 

 withstanding their being as entirely siliceous as those of the hard sinter inside the 

 cup, are too porous and fibrous in their structure to admit of being polished. But 

 the finest specimens of these incrustations are to be found at some of the smaller ori- 

 fices lower down the field, where they are much varied in colour, structure, and 



