50. Mud-Geyser in action. 



51. Boiling Mud Spring. 



52. Grotto Geyser. 



53. Distant view of the Castle Geyser, 



54. Crater of Giant Geyser. 



55. Crater .of the Grand Geyser. 



56. Crater of the Grotto Geyser. 



57. Crater of Old Faithful. 



58. Crater of Castle- Geyser. 



59. Fishpot- Spring in Yellowstone Lake, 



60. The Beehive-Crater. 



61. Mammoth Hot Springs. 



The following 13 are of larger size : 



62. Lake San Cristoval. 



63. View near the head of Lake Fork, of Gunnison River, 

 Colorado. 



64. View on Lake Fork, looking up Snare Creek, Colorado. 



65. The Upper Twin Lake, Colorado. 



66. George Town, Colorado. 



67. Baker's Park and Sultan Mountain. 



68. Gray's Peak from Argentine Pass. 



69. Grand Canon of the Yellowstone. 



70. Falls on the San Miguel, Colorado. 



71. Mammoth Hot Springs, Gardiner's River. 



72. Gateway of the Garden of the Gods, Colorado, Pike's 

 Peak. 



73. The Colorado, or Front Range from near Gold Hill. 



74. Great Falls of the Yellowstone, 



209. Photograph of the great crater of Vesuvius, 

 showing the interior after the eruption of 1872. Size 

 of photograph, 18 in. by 5 in. 



1876. Lent by the late Robert James Mann, M.D. 



This photograph was taken by Mr. J. M. Black, from the gap 

 in the broken edge of the rim. The top of the great rent, extend- 

 ing north and south through one side of the cone to the Atro del 

 Cavallo, is shown on the further side of the crater between the 

 rounded and pointed eminences. 



XI. MISCELLANEOUS. 



210. Models (4) to illustrate the effects of great move- 

 ment on the earth's crust. Made by Dr. Ricketts. See 

 " Geological Magazine," April 1889. 



E. 28 to 31. 1889. Presented by Dr. Riclcetts, F.G.S. 



The position of the consolidated clay is marked by the letter 

 C, while B shows layers of clay originally in horizontal beds, but 



