518 



GEOLOGICAL SURVEY OF THE TEEEITORIES. 



EESULTS COMPILED FROM THE FOREGOING TABLES. 



Tito»ERATUKE. — Temperature has been regarded in the work of ob- 

 servation, and a daily record kept. The greatest heat indicated was 

 970 Fah., August 17, 3.15 p. m., at Boteler^s Ranch, Yellowstone Valley. 

 The greatest cold, 14^ Fah., August 10, sunrise, at Yellowstone Lake. 



Moisture in the Atmosphere. — The record of the wet and dry 

 bulb thermometers furnishes many examples of large differences, indi- 

 cating an extreme dryness of the air. The greatest difference was 

 37JO, (dry-bulb 97°, wet-bulb 59Jo,) August 17, 3.15 p. m., at Boteler's 

 Ranch, Yellowstone Yalley ; elevation, 4,925 feet. 



Rain. — The number of days during which rain fell was 30 : in June, 

 7 ; in July, 11 j in August, 9 5 in September, 2. Observations commen- 

 cing June 10. 



In the foregoing aggregate are included the thunder-storms accompa- 

 nied by rain. The amount of rain which fell was slight in nearly every 

 case. At Evanston we experienced a severe storm of wind and rain, 

 which was attended by a curious rising of the barometer. In fact, so 

 much was it affected as to be totally unreliable in its readings for eleva- 

 tion 5 consequently, it was set aside entirely, and the elevation deter- 

 mined by the Union Pacific Railroad Survey was adopted. 



Thunder-storms. — Five thunder-storms were experienced as fol- 

 lows : three in Juue ; two in July. We recorded distant thunder, indi- 

 cating a storm, upon seven other days 5 in June, 6 ; in August, 1. 



Snow. — Snow fell in small amount at Yellowstone Lake, August 12. 



Hail. — Hail was noted at Boteler's Ranch, August G. 



Frost. — A very heavy frost at Yellowstone Lake, August 13, was 

 recorded. 



Aurora Bore alis.— Only one display of aui'ora borealis was noted, 

 June 17 and 18, and this was not remarkable in its character. 



Direction of wind for the month of June. 



Direction whence - 



I^-. 



KE. 



E. 



S.E. 



S. 



S.W. 



w. 



N.AY. 



Total. 







Kelative number of winds 



7 



6 



1 



8 



8 



10 



5 



7 



52 



Number of observations when there was no 

 wind. 



16 























Direction of wind for the month of July. 



Direction whence 



K 



K".E. 



E. 



S.E. 



S. 



S.W. 



w. 



N.W. 



Total. 







Helative number of winds 



8 



8 



11 







10 



18 



13 



10 



80 



Number of observations when there was no 

 wind . .... .. -. . 



7 























Direction of wind far the motith of August. 



Direction whence 



N. 



N.E. 



E. 



S.E. 



S. 



S.W. 



W. 



N.W. 



Total. 







Heiative number of winds 



9 



12 



8 



3 



8 



19 



10 



5 



74 



Number of observations when there was no 

 wind 



4 























