ORES AT STEAMBOAT SPRINGS. • 345 



Another sample (IV) from tlie same crevices whicli contaiiiod III, hut 

 from a point at wliich steam and sulphureted hydrogen bul)1)Ied tliroiigli 

 the hot water, sliowed an entirely similar composition; it contained mercniy, 

 lead, copper, arsenic, antimony, iron, ahiminiinn, cahiiun, mngiu'sinm, 

 sodium, potassium and lithium, free silica, and free sulphur. The bases 

 were combined as silicates, sulphides, sulphates, carbonates, chlorides, 

 borates, and to a small extent as phosphates. 



S))ecinien V was from one of the springs which had formed a basin, 

 through which occasional bubbles rise to the surface. The sediment con- 

 sisted of layers of gray and j^ellow material, the latter being tinted Ijy 

 sulphide of arsenic. It contained mercury more abundantly than those 

 previously mentioned, and also lead, copper, arsenic, antimony, iron, and 

 aluminium, a trace of cobalt, magnesium, sodium, potassium, cu'sium, lithi- 

 um, free silica, and sulphur. The bases were comljined as silicates, car- 

 bonates, sulphides, sulphates, chlorides, and phosphates. 



At one point on the plateau a mud deposit is formed by deposition 

 from streams issuing from two of the more active springs. Here mica 

 scales exist, showing that in this case some material is brought up in sus- 

 pension from the underlying granite, which must consequently be under- 

 going decomposition ; for the feeble streams of water which rise through 

 it are certainly incapable of wearing granite away at such a rate that the 

 abraded portions would be visible to the naked eye. This mud must there- 

 fore contain products of decomposition of granite, as well as any substances 

 which may have pa.ssed through the granite in solution. (Qualitative 

 nnal3'sis showed that it had nearly the same composition as the other de- 

 posits. The portion soluble in acid contained mercury, gold, silver, lead 

 copper, arsenic, antimony, much iron, aluminium, a trace of cobalt, mag- 

 nesium, calcium, and of course alkalis. The bases Avere com])ined as 

 silicates, carbonates, sulphides, and to a small extent as phosphates. 



A warm spring, which is known as the Chicken Soup Spring, issues at 

 the base of the plateau close to the railway, the water of which is drunk 

 by visitors to the locality. No mercury could be detected in the sedi- 

 ment; but sulphides of arsenic and antimony and free sul[)hur, as well as 

 low vegetable forms, abound in it. 



