PEALE.J 



UPPER GEYSEE BASIN OLD FAITHFUL GEYSER. 



229 



tervals of Old Faithful had increased in 1879. In his report for that 

 year (page 17) he says : 



Old Faithful, tliough still the favorite geyser, has certainly lost prestige by au oc- 

 casioual proloDgation of its intervals between eruptions of from 5 to 15 or 20 minutes 

 during the extreme dry weather of the past season ; but whether it is temporary for 

 want of water, or permanent from change of supply fissures or other causes unknown, 

 time alone will determine. 



He, however, gives no data, and we have already seen that the length 

 of the interval may have a range of nearly 24 minutes.* Dr. S. Weir 

 Mitchell, who was in the Upper Geyser Basin in 1879, gives the average 

 time of the eruptions observed by him at 70 minutes,t which is only 

 about 5 minutes greater than the average of the eruptions observed in 

 1878. He may have observed onlj^ a few eruptions, and they may have 

 had exceiDtionally long intervals. I think that the data are insufficient 

 to show that the geyser is becoming less active, although in the course 

 of time it may follow the example of the Castle, and as its cone becomes 

 larger its intervals may become longer, and a roaring steam period be 

 developed. 



The following table contains the results of the observations made in 

 the different years, which are thus brought together for the purpose of 

 comparison : 



Taile of comparison of oiservations on Old Faithful Geyser. 





Observer. 



q 

 o 



"Sh'o 



o S 

 o 



Intervals. 



q 



<D 2 



+3 



0* q 



Year. 



a 



s 



3 



i 



1 



o 



2 

 o 



a1 



I' 

 1 



LSTO 



Lieutenant Doane 





m. s. 



771. 8. 



m. s. 

 50.0 

 60.0 



m.s. 



5.00 



not given. 



Feet. 

 125 



1870 



Wasbburne 









75 



1871 











138* 



1872 .... 





17 

 11 



65.0 

 52.5 



70.34 

 77.35 



67. 54 

 63.48 



4.53 



4.45 



,5.00 



about 3. 00 



5.00 

 4.35 

 5.00 

 5.00 

 4 to 5. 00 

 5.00 



130* 



1873 







1874 



Dunraven 



100-150 



1875 



Dana and Grinnell 



General Sberman and 



Colonel Poo 



Pealo 



24 



7 

 97 







C65. 

 ] to 



(66.0 



67.0 

 65.6 



70.0 



115* 



1877 



62.0 



54.4 



80.0 

 78.0 





1878 



125-130 

 135* 



1879 



Mitcbell 



150 



1879 



Professor Geike 









120 



1879 



Se guin 









45.0 



197 



1881 



Norris 









175 

















' These heights were measured. 



UPPER SPRINGS. 



Above Old Faithful and the Giantess Group the springs are few in 

 number and are located on the east side of the Fire Hole liiver. I have 

 designated them as the Upper Springs simply for convenience. There 

 are half a dozen basins of small size and one small geyser that spouts 

 about 3 feet. The deposits are brilliant in color, but the springs do not 

 merit more than a reference. Above these the valley narrows to a dee]), 



*In 1831 Prof. Norris says Old Faithful had hourly eruptions of five minutes' dura- 

 tion, the colunms of water reaching a height of 175 feet. See his Report for 1881, 

 p. 50. 



t Lippincott's Magazine, June, 1880, page 702. 



