PEALE.] 



UPPER GEYSER BASIN OF FIEE HOLE RIVER. 



189 



the springs are handsome, and one cnrions fact is the existence of sev- 

 eral bowls of different temperatures in close connection with each other. 



CASCADE aROUP. 



Under this head I inclnde a few springs that are in the bend of the 

 Fire Hole Eiver west of the cascades. One spring or geyser on the east 

 side also may be included. The latter "was named Sentinel Geyser by 

 Colonel Barlow in 1871. He says : 



Here, on either side of the river, are two lively geysers, called the Sentinels. The 

 Que ou the left [east] is in constant agitation, its waters revolving horizontally vt^ith. 

 great violence, and occasionally spouting upward to the height of 20 feet. Enormous 

 masses of steam are ejected. The crater of this geyser is 3 feet by 10. The opposite 

 Sentinel is not so constantly active and is smaller.* 



The latter is seen in Plate 15, the distant column of steam showing 

 its location. The springs on the western side of the river are separated 

 from the springs of the Grotto Group by alow hill. They are some ten 

 in number, and have temperatures from 170° F. to 192° ; some are 

 boilers, and others are quiet. The principal spring is the Cyclops 

 Spring, which is a magnificent spring 50 by 60 feet, and of great depth. 

 It has a temperature of 170° F. 



GROTTO GROUP. 



Under this head I have included all the springs in the neighborhood 

 of the Grotto Geyser, on both sides of the river. They occupy an area 

 of about 800 square yards, and have among them two first-class gey- 

 sers. The springs are, with the exception of 'No. 17, not remarkable 

 for beauty, nor of any special interest. The mound on which they are 

 situated is partially overgrown with trees, which sei^arate the majority 

 of the springs from the cones of the Grotto Geyser. Our time for the 

 examination of the group was small, and w^e were unable to devote any 

 time to the observation of the geysers. The latter are not in sight from 

 the other parts of the basin, aud the facts presented are therefore small 

 as compared with those given in the descriptions of the other groups. 

 The table presents most of the facts noted in the case of the springs, 

 and from the description there given the different springs can be recog- 

 nized. 



Tahle of the Grotto Group. 



Number or name. 



2. Grotto Geyser. 



3 



4 

 6 



Size and depth. 



Basin 28 feet diameter. 



a3by 5feet 



6 3 feet diameter 



Large cone 8 feet bi{j;h, 



orifice 'i by C feet and 



19 feet d(!ep. 

 Small cone is 4 feet high, 



orifice 3 by 5 feet, 10 



feet deep. 

 19 by 9 to 17 feet 



6by7feet 



Orifice 18 inches by 1 

 foot. 



Temper- 

 atuie. 



al80 

 &175 

 198° 



196° 



tl98 



190 

 133 



Kemarts. 



Two openings in one basin; a 

 is double. 



See text for full description. 



Inky-green pool constantly 



boiling at one end. It is a 



pulsating s])ring. 

 Almiist constant bubbler, with 



cousifb'iublo overflow, 

 nolo in tlio watcroutlet of the 



grotto fioin which it ro- 



ccives water. 



"Reconnaissance of the Yellowstone River, 1871, p. 25. 

 1 14 feet below the surface it is 199"^. 



