180 EEPOET UNITED STATES GEOLOGICAL SURVEY, 



Taile of Half-ivay Group or Egeria Springs — Continued. 



Name or number. 



Size of spring. 



S 

 m 



Time of obser- 

 vation. 



g 



Eemarks. 



22 



2 boles, each 1 foot diam- 



eter. 

 6 inches by 1 foot 



3 by 8 feet 



-p. 



160 

 160 

 186 



190 



184 

 150 



180 



183 

 197 

 195 



179 

 191 



194 



( 197 



^al96 



(6 185 



171 



195 



156 

 163 









23 



2p. m 



59 



Small white hole with white 



24 



scalloped border. 



Clear spring with black and 

 gray basin; spouts at one 

 end, splashing against the 

 other. 



Gray and white spring with 

 two white iunnel holes. 



Deep white fluted basin with 

 trianguloj funnel and green 

 water. 



Chimney.like hole in hard de- 

 posit. 



Large blue cavern. 



25 



2 by 5 feet 







26 



20 by 25 feet 







27 



















a 5 feet diameter 



25 by 28 feet 













29 







Gray basin with white edge. 



30 



40 by 50 feet 







There is a deep blue cavern 

 at one end. 

 Green cavern-like spring 15 to 

 20 feet below the surface. 



31. Pebble Spring 



32. Catfish Gey- 

 ser of 1871. 



Flat basin 6 feet diam- 

 eter. 



Cone 5 feet high 



Basin 8 feet diameter ... 

 1 











spouts 6 inches or a foot 

 from a hole 3 inches in diam- 

 eter. 

 Horn -like fissure. Spouts 6 

 inches to a foot. 













) Bubbler like No. 31. Orifice 









I is about a foot in diameter. 



34 









35 





3.30 p.m.. 



56 



Bulging spriug at the foot of 

 the bluff. Steam comes out 

 in large bubbles. 



Tellowish-green spring. 



Gray spring on edge oi' river. 



36 





37 

















39 



Pool 























DESCRIPTION. 



IsTo. 1. Grand Prismatic Spring. — This is perhaps the handsomest 

 spring in the whole Park, and it is certainly one of the largest, if not 

 the largest. It measures 250 by 350 feet. I have named it Prismatic 

 on account of the brilliant coloring displayed in it. The steam gener- 

 ally obscures the view, bnt the best point to see it is from the point of 

 the bluff on the opposite side of the river. Over the central pit or bowl, 

 which is constantly boiling and sending up vast columns of steam, the 

 color is a deep blue, which fades into green towards the edge. The sur- 

 rounding shallower basin has a yellow tint, fading into orange, and out- 

 side the rim is a brilhant red deposit. This fades into purples, browns, 

 and grays, the whole being on the gray-white ground of the deposit, 

 forming the mound on which the spring is situated. These colors are 

 vivid and perfectly distinct, '^o imagination is needed to distinguish 

 them, but they stand out in well-marked bands. 



When we visited these sj>rings in 1871, JMr. Thomas Moran, the artist, 

 accompanied us, and made water-color sketches of the springs, which 

 show these vivid colors, as did also Mr. W. H. Holmes. As time elapsed 

 after our return our recollection of the coloring naturally became less 

 and less distinct, and we began to think perhaps the colors shown in the 



