260 



EEPOET UNITED STATES GEOLOGICAL SURVEY. 



The only temperature taken in 1872 was 198° F. It was found impos- 

 sible to take the temperature immediately preceding the eruption, as 

 the agitation of the water was too great. The table shows that the 

 temperature of the air has no appreciable effect on the temperature of 

 the water in the geyser, as with some of the lowest air temperatures the 

 highest temperatures were observed in the geyser. The surface tem- 

 jjerature shows a gradual rise from the 17th to the evening of the 20th, 

 an eruption taking place the following morning. These temperatures, 

 with the exception of the first (196° F.), are either close to or above 

 the theoretical boiling-point, which is 198.2° F., as deduced from hirty-six 

 barometrical readings. The boiling-point, obtained by plunging the 

 thermometer in boiling water, in camp, is about a tenth of a degree 

 lower than the theoretical x>oint just given. It is evident, then, that the 

 water in the geyser is superheated by the steam from the depths below, 

 which escapes through the water. The deep temperatures (which are 

 the deepest obtainable) also show a gradual increase at first and then 

 a maintenance of 208° F. for a couple of days before the eruption. After 

 the eruption it rose again steadily to 207° and it is probable if the tem- 

 peratures had been observed later 208° might have been observed. 



CAMP GROUP. 



This group includes a few springs near the river, which were near 

 our camp. They are enumerated in the following table : 



ITo. and 

 name. 



Size and depth of 

 spring. 



a 



Deep tempera- 

 tures. 



a 



P-Vl 



a° 



H 



Time of 

 observa- 

 tion. 



Eemarka. 



1. Wash-tub. 

 2 



12 by 9 feet; basin 

 ej'feet deep. 



4 by 5 feet ;3J feet 

 deep. 



3 by 3 feet ; basin 

 2 "feet deep. 



3 by 3 feet 



5 by 2 feet ; 6J feet 

 deep. 



8 by 15 inches ; 2| 

 feet deep. 



i:9 



159 



192 



190 

 166 



(*) 



5 feet below sur- 

 face in the basin, 

 177. 



6 feet below sur- 

 face at tube, 185. 



2J feet down, 159 .. 



6 inches below 

 suriace, 194. 



°F. 

 63" 



64 



63 



62 

 63. 



1.50 p. m. 



2.00 p. m. 

 2.10 p. m. 

 2.15 p. m. 



Large yellow-linedbasin, 

 with a tube leading 

 downward from it. 

 It was used as awash- 

 tub. 



Bather quiet spring, with 



3 



drab-colored deposit ; 

 a few bubbles escape 

 occasionally. 

 The water is 8 inches be- 



4. Lavender 



spring. 

 5 



low the top and is in 

 constant agitation, 

 spouting about a foot. 

 Mud spring, with thin, 

 boiling mud. 



5 feet below the 

 surface, 168. 



There are two openings 



g 





to the main spring, 

 and near it are two 

 vents. 

 An old geyser mound 



7 









and tube, evidently 

 full of water at times ; 

 near it is an extinct 

 crater. 

 Hole in the side of the 













hiU. 



* Not taken. 

 MINUTE MAN GROUP. 



The Minute Man Group is on the east side of Shoshone Creek, about 

 500 or 600 feet north of the Orion Group. The Minute Man Geyser, from 

 which the group is named, is about in the center of the group, and is 



