162 REPOET UNITED STATES GEOLOGICAL SURVEY. 



DESCRIPTION. 



ISTo. 1 includes a lot of small springs, mostly round and flat, without 

 marked rims. There are also pools of standing water, with red linings, 

 a is a thumping spring. Temperatures in this cluster in 1871 were 

 162° F., 175° F., 1620 F., 153o F. Between this cluster and the White 

 Dome are two red-lined springs at the edge of the mound of deposit 

 that surrounds the White Dome, and on the platform of the latter, prin- 

 cipally on the northwest side, are a number of holes and steam vents. 



White Dome Geyser. — (Plate IX.) This rather dilapidated cone repre- 

 sents the condition of old age in a geyser, its deposits being soft and 

 crumbling, evidently decaying. It is about 25 feet in height, resting on 

 a platform of deposit. Steam escapes from the sides and from the ori- 

 fice on top. It spouts irregularly about 5 or 6 feet, occasionally reaching 

 10 or 12 feet. There is very little water ejected, steam mingled with 

 spray predominating. The geyser is evidently in a state of decay, and 

 the deposits are diEgy-gray in color. An old channel shows that once it 

 was a powerful geyser. Steam escapes with gentle force almost con- 

 stantly. No temperature was obtained, as the water was too far below the 

 top to be readily measured. Professor Oomstock gives the following 

 description of the deposits of the Dome: 



The material of the mound at this point is a very compact, flinty variety of geyser' 

 ite, arranged irregularly in plates, witli a clear opal appearing in spots. The exterior 

 is covered with a dark-brown growth of a scummy substance, which turns black upon 

 drying, and a perceptible pink tinge, with a few touches of green, are found beneath 

 and in patches. The recent mechanical deposits about the mouth of the chimney are 

 compactly granular, breaking i-eadily into coarse, uneven joints along no particular 

 lines. The surface contour is irregular, and the whole, when wet, has very much the 

 appearance of a mass of white commercial sponge of a mixed variety, i. e., an average 

 mass with frequent spots of a very fine-pored variety. In an ordinary light, small 

 pieces sometimes have a dingy aspect,much like the color of coarse granular salt recently 

 removed from a saturated greasy brine, but this changes to au extremely delicate 

 pinkish hue in the full play of the sunlight.* 



No. 2 marks the site of several cones and springs on the platform a 

 little east of south from the " White Dome." The water in the cones was 

 below the surface when examined. One of them spurts water and steam 

 in a jet to the height of 3 or 4 feet. One of the springs (b) has a basin 

 7 feet in diameter, in which, 2 feet below the surface, at the bottom of a 

 globular-edged cavity, there is an orifice a foot in diameter. This is 

 orange-colored, and from it the water comes in bulges, with a tempera- 

 ture of 19G° F. The surface of the platform in several places near these 

 springhs as caved in. 



No. 3 is a collection of holes in the surface west of the Great Fount- 

 ain, with very high temperatures (200^201° F.). 



Great Fountain or Architectural Geyser. — (Plates X and XI.) This 

 geyser was named Architectural in 1871 and renamed the Great Fount- 

 ain in 1872, which is by far the preferable name, and the one that will 

 probably be retained. It is probably the unknown geyser of Professor 

 Oomstock (see p. 248 of his report). It is a bowl or basin on a platform 

 of geyserite, which is composed of beautifully ornamented geyserite, 

 well shown in Plate XI. The following description by Mr. W. H. ilolmes 

 is taken from my report for 1872 (p. 144) : 



During our somewhat protracted s+ay in the lower basin I found time to observe 

 pretty carefully all the geysers of any considerable importance. Among the six or 

 eight which throw columns of water to the height, say, of 30 feet, there is only one that 

 possesses the dignity and grandeur of the great geysers of the Upper Basin. Although, 



* Report of Reconnaissance of Northwestern Wyoning in 1873, p. 247. 



