GEOLOGICAL SUEVEY OF THE TEREITOEIES. 



123 



sending ont huge masses of steam, causing a general stampede of our 

 company, driving us some distance from our point of observation. 

 When within about 40 feet of the surface, it became stationary, and 

 we returned to look down upon it. It was foaming and surging at a 

 terrible rate, occasionally emitting small jets of hot water nearly to the 

 mouth of the orifice. All at once it seemed seized with a fearful spasm, 

 and rose with incredible rapidity, hardly affording us time to liee to a 

 safe distance, when it burst from the orifice with terrific momentum, 

 rising in a column the full size of this immense aperture to the height 

 of 60 feet; and through and out of the apex of this vast aqueous 

 mass, five or six lesser jets or round columns of water, varying in 

 size from 6 to 15 inches in diameter, were projected to the marvelous 

 height of 250 feet. These lesser jets, so much higher than the main 

 column, and shooting through it, doubtless proceed from auxiliary 

 pipes leading into the principal orifice near the bottom, where the explo- 

 sive force is greater. If the theory that water by constant boiling be- 

 comes explosive when freed from air be true, this theory rationally ac- 

 counts for all irregularities in the erui^tions of the geysers. 



Fig. 58. 



THE GIANT. 



This grand eruption continued for twenty minutes, and was the most 

 magnificent sight we ever witnessed. We were standing on the side of 

 the geyser nearest the sun, the gleams of which filled the sparkling col- 

 umn of water and spray with myriads of rainbows, whose arches were 

 constantly changing — dipping and fluttering hither and thither, and 

 disappearing only to be succeeded by others, again and again, amid the 

 aqueous column, while the minute globules into which the spent jets 

 were diffused when falling sparkled like a shower of diamonds, and 

 around every shadow which the denser clouds of vapor, interrupting the 

 sun's rays, cast upon the column, could be seen a luminous circle radiant 

 with all the colors of the prism, and resembling the halo of glory repre- 

 sented in paintings as encircling the head of Divinity. All that we 

 had previously witnessed seemed tame in comparison with the perfect 

 grandeur and beauty of this display. Two of these wonderful eruptions 

 occurred during the twenty-two hours we remained in the valley. This 

 geyser we named "The Giantess." (Fig. 59.) 



