FEALE.] 



UPPER GEYSEE BASIN CASTLE GEOUP. 



207 



105 feet. 2.5 p. m. The water period is ended, and the steam escapes 

 with steady thumpiugs. After some time there are periods of deep 

 rumbling and thundering, after which the steam escapes with great 

 violence. The steady roar can be heard in all parts of the Basin. 3.5 

 p. m. The steam is escaping very gently. 3.9.45 p. m. There is a slight 

 roaring, lasting three-quarters of a minute, when the eruption is over. 



August 29. — 9.45.20 a. m. The Castle begins throwing water in irreg- 

 ular spurts ; the height was not measured. 10.12.30 a. m. The steam 

 begins to come out with a thumping noise. 10.21 a. m. The steam ap- 

 pears to be propelled in jets at intervals. 10.46.45 a. m. The eruption 

 is at an end, and the steam is coming out as usual. 



August 31. — 8.45 a. m. There are several violent spurts from the 

 crater, which lasted altogether 3 minutes 30 seconds. 8,49 a. m. Spurts 

 began again, and in 30 seconds reached a height of 50 feet ; then slowly 

 sank, with steam intervals, until 8.50 a. m., when there was a violent 

 spurt for a minute, followed by steam, after which there were occasional 

 spurts at intervals of 10 to 60 seconds until 10.10 a. m., when the inter- 

 vals became longer. These kept up during nearly the whole day, and 

 probably represent the continuous action of the geyser in the intervals 

 of the eruptions. 



September 9.— During the night there was an eruptioUj but the time 

 was not known. 12.39.25 p. m. An eruption began which reached a 

 maximum height of 88 feet. 12.49 p. m. The steam eruption begins. 

 The end of the steam period was not noted, as we were obliged to go to 

 another portion of the Basin before it was ended. 



The notes taken on the 31st of August were not those of an eruption, 

 but of the constant action. None of the eruptions witnessed equaled 

 the one noted by Dunraven in 1874. The escape of steam from the 

 crater was so great that I did not succeed in obtaining any tempera- 

 tures. 



The following table composes all the eruptions that have been re- 

 corded. I include only those in which the steam period is noted as 

 occurring after the water-spouting : 



Date. 



Observer. 









tM 





-2 





O 









a 





&: . 





.2q 



No. 







1-B 





•n^ 





1X3 p 





2 





-a® 









o 





fl 





H 





m. 8. 



h. 



m. 8. 



1 









2 



15 00 



1 



22 00+ 



H 



10 00 







1 



10 00 



1 



00 00 + 



1 



20 00 



1 



00 00+ 



1 



15 00 



1 



50 30 



2 



27 10 



1 



1 25 



3 



9 35 











Maxinmin height 

 of water eruption. 



Aug. 18, 1872 

 Aug. 18, 1872 

 Aug. 18, 1872 

 Aug. 2.3, 1873 

 Aug. 25, 1874 

 Aug. 28, 1878 

 Aug. 29, 1878 

 Sept. 9, 1878 



A.C.Peale 



do 



do 



Prof. Thco. B. Comstock . 



Earl Dunraven 



A.C.Peale 



do 



do 



34 feet, measured. 

 93 feet, measured. 

 51 feet, measured. 

 30 feet, estimated. 

 250 feet, estimated 

 105 feet, measuixMl. 



88 feet, measured. 



The observations are tooisolated to determine the interval of the geyser. 

 The points we have recorded prove that, besides the eruptive action, 

 which has a well-defined course of procedure, there is a state of constant 

 activity, which is accompanied by spurts, which reach 50 feet, or even 

 60 feet, as seen in 1870 by Doane and Langibrd. They, however, did 

 not see a genuine eruption, in which the steam period is the most marked 

 feature, and forms the peculiarity of the action of the Castle. There 



