PEALE.] 



LOWER GEYSER BASIN EGERIA SPRINGS. 



185 



close to the trail and^ gives constant exhibitions, althongh the height 

 to which the water is thrown is not great ; 20 feet, perhai3s, being the 

 maximum. 



I saw two eruptions on October 9, separated by an interval of 50 

 minutes, the first occurring at 1.35 p. m., and the second at 2.25 p. m. 

 On the 11th I saw the following eruptions : 



No. 



Time of be- 

 ginning. 



11.30 a. m - 

 ].39p. m- 

 2.20 p.m. 

 3.00 p.m. 

 3.40p. m- 



Interval. 



41 minutes. 

 40 minutes. 

 40 minutes. 



The eruptions therefore appear to occur with considerable regularity. 

 They last G or 7 minutes, and the average height of the column is not 

 more than 5 feet. 



In Plate XIII a we have a general view of the plateau of geyserite, 

 on the left bank of the river, upon which most of the springs are sit- 

 uated. The view is from a photograph taken from a point opposite the 

 bend in the river, and looks a little west of north, showing north Twin 

 Butte in the distance. Almost on a hue with it, a little to the right, is 

 the Grand Prismatic Spring, indicated by a faint cloud of steam, and 

 still farther to the right is the steam rising from the Cliff Caldron. The 

 position of the other springs will be apparent on comparing the illustra- 

 tion with the accompanying map, on which the springs are indicated 

 by their numbers. 



BABBIT BRANCH SPRINGS. 



Eabbit Branch is a small hot creek which flows into the Fire Hole 

 at the lower or south end of the Egeria or Halfway Springs. It rises 

 by two branches in ravines east of the Egeria Group and south of the 

 Fifth or White Dome Group. Each of these ravines is the seat of 

 active hot springs. They were not visited in 1871, but were seen in 

 1872 and 1878. It was my intention to visit them in this latter year, 

 but I was obliged to leave the Lower Basin before the work was com- 

 pleted, and I therefore give the description of the springs given by 

 Professor Bradley in the report for 1872, as he is the only one who has 

 visited them. The springs at the mouth of the creek are included with 

 the Egeria Si)rings and are shown on the map of that grou]). The 

 whole stream is lined with warm and hot springs, but there are two 

 principal groups, the northern and the southern. 



Northern Group. — The principal one [spring] at the head of the northern foi'lc, <t> 

 large s'eaniiiig pool, reaches 148°, and is not surpassed by any of its neighbors. About 

 the forks of the stream a considerable cluster of steam vents, pools, and mud pots give 

 various temperatures up to IHG'-' and 192°; yet, as a whole, the group shows but little 

 activity. Steam vents and small pools run far up the side of the mountain. 



Southern Group. — At the head of the,southoru fork, separated from the last group 

 by from 200 to 300 yards of timber, is a cluster of )uostly small springs, which show 

 rather greater activity. The ]trincipal vent is situated under the precipitous bank, 

 and is apparently working backward by undermining the overhanging rock. Largo 

 masses have already sli])i)ed off and fallen into the narrow pool, so as to greatly iu- 

 terf(!re with the free motion of the water ; and, accordingly, thougli steaming and 

 boiling furiously, it spatters onl,y a short distance. It Avas impossible to reach the 

 boiling center; the nearest accessible part of the pool gave a tcmpcnil uro of 192°. 

 Crossing the spur to the southward w(! found instead of a broad Hat vailc'y, like the 

 one we had just left, a narrow, steep ravine, partly with i)recipitou8 sides, at only one 



