142 GEOLOGICAL SURVEY OF THE TERRITORIES. 



marshy aud full of springs, which cause the water in the stream to 

 have a temperature of some degrees more warmth l5ian the air. We fol- 

 lowed the river to within some four miles of the lower geyser- basin, 

 and camped at a level some SG7 feet lower than the divide and 452 feet 

 lower than our camp (No. 12) at ]\Ind Volcanoes, having traveled ume- 

 teen miles. Some of the party who had preceded us a day came into 

 camp in the evening and reported that they had met the advance- 

 party of the Snake lliver division of the expedition, under Mr. Steven- 

 son, so the following morning we moVed down into the lower basin, and 

 in the evening found that the main body of the Snake River division 

 were encamped within a mile of us, having got in about the same time 

 we did. The next day they moved their camp and joined lis. 



On the way from camp we passed a number of unimportant springs, 

 which I will incorporate in the catalogue ai)pended to my report. 1 shall 

 devote but little space to the springs of the lower geyser- basin, as they 

 were referred to at length in the report last year, louring the three days 

 and a half that 1 was in the lower geyser-basin this year, I was occupied 

 most of the time in packing specimens to be sent to Virginia City, so 

 that I was able to \isit but one group of si)rings. As this, however, is a 

 typical group, I will insert the descri[)tion. They are situated just south 

 of camp ill an open space bounded on two sides by timber, while the front 

 looks out into the main open basin. They occupy a space of a little over 

 3,000 square yards. The springs are as ibllows: 



Gourd Spring. — This spring was named from its shape. It is in the 

 center of a large, circular mound of siliceous material, and is 15 feet long 

 by 10 feet wide and 12 feet in depth. The bed of the small stream, car- 

 rying away the overliow from the s])ring is coated with iron, aud a short 

 distance below we find the gelatinous material that we see in so many 

 of the springs that have a low temperature. The temperature of the 

 water in the spring was 171<^ F.; air, 02° F., at 9 a. m. 



Thud Sprhuj. — This spring is o75 feet southwest from the Gourd, and 

 measures 18 feet by IG feet. The depth varies from 8 to 13 feet. This 

 of course refers only to the basin of the spring, as at the bottom there 

 are oritices the dei»th of which cannot be ascertained by the line. There 

 seem to be three centers of ebullition, two of which are vei^' active. At 

 intervals of afew minutes there seems to be an accumulation of steam, 

 the escape of which shakes the ground, making a thud-like noise, wltence 

 its name. On looking into this spring the water seems to have an inky- 

 green color, and had a temperature of 102° F.; air, 62° F., at 9.30 a. m. 



Oah Leaf Spriitf/. — This si)ring is 345 feet north of the spring next 

 described. The det>osit about it has a gray color, and the margin of 

 the spring has the appearance of being fringed with oak-leaves. The 

 spring is about G feet in diameter and 15 feet deep. The water ap]>ears 

 of a greenish color and has a temperature of 194° F.; air, C4° F., at 10.35 

 a. m. About 7 feet from this spring there is a small cone of 2 feet 

 diameter, rising five inches above the surrounding level. The tempe- 

 rature of the water in this cone was 190° F. 



Fungoid /Spring. — This spring is 140 feet west of the Thud Spring, and 

 345 feet south of the spring described above. The basin of this si)ring 

 measures 13 feet by 17 ieet and averages 6 inches in dejith. The de- 

 ])0sit is ]mr('-white siliceous sinter, giving it tlie appearance of a marble 

 basin. In the center of this basin there is another 5 feet in diameter .aiid 

 7 feet deep. Here the water has a greenish tinge, which forms a pretty 

 contrast with the white rim outside. The spring hns a margin of the 

 siliceous material that resembles a row of I'ungoid growths on short ])e- 

 destals. There are two small streams proceeding from the. spring, which 



