264 EEPOET UNITED STATES GEOLOGICAL SUEVEY. 



The following temxieratures were taken, all on tlie 16th of August, 

 with the air at 60° F. 



1 3 p. m., 196° F. at the surface; 196 Jo F. 4 feet below. 



1 16 p. m., 196J° F. at surface, just before the basin is full. 



1 22 p. m., 197° F. 2 feet below the surface. 



The outlet from the Shield is brilliant white and lined with pearly- 

 pebbles. When the spring is in action there is considerable overflow, 

 which runs towards the Kosette. 



Gourd Geyser. — The Gourd, shown in the foreground of Plate XXXII a, 

 was named from its shape. It is close to the Shield, with which it 

 appears to be in sympathy. Whenever the water was low in the former 

 it was lower than usual in the Gourd, although the boiling continued. 

 The opening is irregular, having a length of about 8 feet. The crater 

 is 10 feet long. The broad portion of the gourd-shaped opening is about 

 5 feet in diameter, while the narrow neck and crooked portion measure 

 from about 1 foot to 2 feet in width. Globular masses line the neck, 

 and beyond the end are flat basins in which the water stands. It is 

 constantly boiling, the points of ebullition being mainly in the broad 

 portion of the gourd. It is doubtful if there is any sympathy between 

 the Minute Man and either the Shield or Gourd. 



The following temperatures were taken August 16, with the air at 

 60° F.: 



o Y. 

 Surface 196 



5 feet below the surface 199 



7 feet below the surface 200 



The last temperature was taken in rather quieter water than were the 

 others. The amount of steam escaping from the Gourd appeared to be 

 greater than that from the Shield. The amount of depression in the 

 water of the Gourd was always rather slight. 



Rosette Spring. — This spring was named in 1872, and lies between the 

 Shield and the hill. It is a beautiful, cavern-like spring, 30 feet long 

 and 17 feet wide at the widest part, and 13 feet deep. The border is 

 rosette-bordered, as is the outlet. The opening of the spring is about 

 half the size just given. The colors of the spring are blue, green, and 

 greenish -blue. The lining of the basin is arranged in scalloped scales, 

 overlapping like scales in a coat of mail. On these scales was a coating 

 of sulphur, the color of which increased the beauty of the spring. In 

 the shallower basin the tints were light-pearl and blue-grays, fading 

 into pinkish-pearl grays. The spring, whenever noticed, was quiet and 

 had a surface temperature of 166|o F. at 1.30 p. m., air 59° F. The 

 temperature at a depth of 7 feet was the same as at the surface. Back 

 of the Kosette is another pool of about the same size, viz, 30 by 18^ feet. 

 It has a rather shallow basin, lined with a leather-like deposit. The 

 temperature was only 149° F. 



On the flat space at the foot of the hill, back of this pool, there were 

 several bubbling points. 



The hill back of the Minute Man also has a number of steam vents 

 and hot holes. 



Xo. 15. The Little Bulger Geyser. — This geyser, which is across a small 

 knoll from the Eosette, was called the Bulging Spring in 1872. I have 

 renamed it as a true geyser, although not a very large one. It has a 

 flat, depressed basin, about 11 by 15 feet, from which a beautiful yellow- 

 lined outlet or water way takes the overflow when the geyser is in action. 

 In the center of this basin the opening is Sh feet in diameter, very rapidly 

 diminishing in size downward. The following notes on the eruptions 



