PEALE.] LOWER GEYSER BASIN FISSURE GROUP. 159 



says it sports from 2 to 10 feet high for from 65 to 80 seconds, with quiet 

 intervals of about the same length. Professor Comstock, who saw it in 

 1873, says it spouted irregularly, with active and quiescent epochs of 

 one or two minutes' duration, and gives the height as 3 to nearly 10 feet. 

 I estimated the height as 5, 10, and 15 feet. It is doubtful if it ever ex- 

 ceeds 20 feet. Beyond the geyser is a red pool, and back of it a small 

 geyser which I have named. 



^o. 34. Gray Bulger. — It spurts to the height of a few inches only at 

 intervals of 45 to 60 seconds, the spoutings or bulgings lasting from 30 

 U) 40 seconds. 



At the east end of the lake is a collection of springs (ISTos. 35 to 39), 

 which do not merit specific description. Several of them are boiling 

 springs. Beyond them is a brownish laminated rock which appears to 

 he an old spring deposit. 



On the north side of the lake, opposite Young Hopefal, are several 

 unimportant springs (Nos. 41 to 43), and a number of holes in the grass. 



Returning now to the Lower Lake, we find in the timber on the edge of 

 the ravine or valley south of the Steady Geyser a circular, green-lined, 

 spring (No. 44), and stOl farther west a collection of sulphur springs 

 {Nos. 45 to 47). The sandstone deposits near this latter cluster are honey- 

 combed and riddled like the sandstones near some of the springs in the 

 Shoshone Basin. Professor Bradley found similar perforated sand- 

 stones near the Architectural Geyser or Great Fountain in the Fifth 

 Group just South of the locality in which these springs occur. He thinks 

 that it represents on a small scale the process by which the basins of 

 the springs are fonned.* 



Crossing now to the north side of the valley below the terraces, and 

 skirting the hills on that side as we go to the westward and northward 

 towards the Fountain Group, we find four interesting springs (Kos. 48 to 

 51), which I have included in this group. 



No. 48 is a x)ink-beaded basin 25 feet in diameter on the outside and 

 15 feet in the inner basin. The water was 10 feet below the top, and 

 had a temjjerature of 186° F. The basin and throat of this geyser are 

 beautifully frosted and beaded. The orifice is triangular, measuring 3 

 feet on the sides. The height to which it spouts is 15 or 20 feet, as ob- 

 served on the one occasion on which it was seen in action. Farther 

 along is No. 49, a cone with a triangular orifice. Northwest of the latter 

 is No. 50, a white mound spring with yellow edge; steam escapes with 

 a thumping noise. 



No. 51 is a beautiful white basin (5 by 6 feet) with two openings, one 18 

 inches in diameter and the other 8. The latter (a) bulges, and has a 

 temperature of 196'^ F., while the former is 186° F. The water rises and 

 falls in the basin in pulsations. 



FIFTH OR WHITE DOME GROUP. 



South of the springs last described, under the fourth group, is a wide, 

 flat area, partly marshy and covered with broken geyserite, o\'er which 

 an intricate network of small streams from the Fissure Group inter- 

 lace with others coming from the south, and which have their origin in a 

 group of springs surrounding a cone that forms a conspicuous object in 

 the landscape. This cone was named the White Dome Geyser in 1871, 

 and trom it the group of springs is named. South of it the valley nar- 

 rows into a ravine, which is lined with hot springs, which I have in. 



* Sc6 Report of U. S. Geol. Survey for 187^, p. 235. 



