116 EEPOET UNITED STATES GEOLOGICAL SURVEY. 



not unlike the sound produced by the escape of steam from the cylinders of a locomo- 

 tive moving slowly. For puri^oses of distinction this will here be called the Locomo- 

 tive Spring.* 



There are besides a number of other steam vents, but the two de- 

 scribed are the principal ones and are typical of the others. 



Professor Oomstock is of the opinion that the action of the waves on 

 the point is gradually converting the Steamboat and other springs into 

 Locomotive Springs, and the latter into boiling springs in the lake, 

 where there are already several. Steamboat Point probably once ex- 

 tended out into the lake as far as Pelican's Eoost, which is now an island 

 about half a mile from the present point. The lake has probably worn 

 away the intervening portion, which it might do readily, as the deposits 

 which form the poiut are soft and friable. Several huudred yards back 

 of the point, on the south side, there is a small group of mud springs, in 

 which the mud is of a pure white color. Dr. Heizmann, in 1873, took 

 temperatures at Steamy Point, and writes : 



Steamy Point, covered with large vegetable growth, contained a small number of 

 springs (184°-192°), all bubbling violently, and a few holes in the side of a rocky bauk, 

 from which issued jets of steam, but little water, depositing a yellowish brown on the 

 surface. At times, irregularly, the puffing steam was more violent than at others. 

 The ground about these was insecure, as about the mud sxjriugs.t 



He gives the temperature of another spring as 192°. 



The principal constituents of the deposits at Steamboat Point are sul- 

 phur, silica, iron, and alumina, and sulphureted hydrogen is the prin- 

 cipal gas, although it is not so abundant as at Turbid Lake. Professor 

 Comstock mentions carbonic acid as having been given off from the 

 dried mud from one of the springs when treated with chlorhydric acid, 

 but it was not present in great quautity.| 



MARY'S BAY GROUP. 



By this name I have designated the group situated on the northeast 

 side of Mary's Bay, about 2 miles beyond Steamboat Point. The first 

 spring met with on the way from the point toward Pelican Creek is a 

 turbid spring, at the end of a small lake-like pool. It had a temperature 

 of 183° F. A short distance beyond are three boiling springs, with 

 temperatures of 185° F. to 186° F. Near there is a second small pool, 

 with several springs at the north end, having temperatures of 178° F. 

 One of them is a black, boiling spring. Beyond these, near the lake 

 shore, are two springs, one a turbid boiling spring, with a temperature 

 of 180° F. North of these two is a white sand spring, the temperature of 

 which is also 180° F. 



These springs were visited in 1873 by Dr. Heizmann, who writes of 

 them as follows : 



Between the mouth of Pelican Creek and Steamy Point, on the shore of the lake, is 

 a chain of springs (100°-192°), some steaming, most of them with lead-colored deposit 

 and water, all bubbling carbolic acid, and only some sulphureted hydrogen. In one 

 I noticed the gases rising from small holes similar to those of the springs at camp 37 

 [at the head of Pine Creek], and from the top of little cones in its bottom. One, 

 (106°), the largest, and like Turbid Lake, a reservoir, bubbled along its shore, while 

 its banks were filled, like it, with small active and remains of small extinct springs; 

 one 20 feet from the last, 3 feet in diameter, temperature 120°, lead-colored deposit, 

 reacted for sulphureted hydrogen, iron, alumina, and soda, sulphides, sulphates, and 

 hyposulphites, and became very acid after standing four hours. § 



* Report of Reconnaissance of N. W. Wyoming, by Capt. W. A. Jones, in 1873, p. 19'2. 

 t Report of Reconnaissance of N. W. Wyoming, by Capt. W. A. Jones, in lb73, p. 298 ; 

 t Ihicl, p. 192. 

 § Report of Reconnaissance of N. W. Wyoming, by Capt. "W. A. Jones, 1873, p. 298. 



