262 PROCEEDINGS OF THE COTTESWOLD CLUB 



exquisite ornamentation of the hot springs and pools 

 which abound along the Firehole River Valley. I brought 

 away a few small specimens of this " geysirite " as it is 

 termed, which are on the table before you ; but I was not 

 vandal enough to knock away any of the delicately-carved, 

 flower-like forms which are seen everywhere glittering 

 through the clear blue water in the pools. I preferred to 

 leave this practice to vulgar tourists, who are now, I am 

 glad to say, debarred from it by a strictly-enforced law. 



The same deposit takes place, even without evaporation, 

 when appropriate nuclei such as leaves, or sticks, or 

 insects, are immersed in the water. Butterflies, for 

 instance, which fall on the surface and are killed by the 

 boiling water, are in a few hours encased in a thin film of 

 silica, like the petrifactions of calcium carbonate which are 

 so common at Matlock, and abound in greater beauty and 

 profusion in Auvergne. 



I must not omit to mention another cause which con- 

 tributes greatly to the attractiveness of the deposits in the 

 hot springs and geysir pools. Certain kinds of coloured 

 algae are found to flourish luxuriantly in water at tempera- 

 tures as high as 90° C. (194° Fahr.) ; and several of 

 these have, Hke the common marine corallines, the power 

 of assimilating calcareous and siliceous materials from the 

 water, and armour-plating themselves, as it were, with a 

 thick covering of stone. Thus we have in water nearly 

 hot enough to boil a cabbage for the table, masses of 

 organic and inorganic vegetation wonderfully intricate and 

 beautiful in form, coloured with every conceivable shade 

 of green, yellow, pink, red, and brown. 



With this short explanation of the chief physical char- 

 acteristics of the Yellowstone district, I may pass on 

 to describe what I saw myself during a too brief visit to 

 it. [Diagram shown]. The general plan of the Park 

 being an elevated plateau 60 miles square (about half the 

 size of Wales), and averaging about 8,000 feet above sea- 

 level, surrounded by mountain ranges rising about 3,000 



