1890-91.] GOLD AND SILVER IN GALENA AND IRON PYRITES. 123 



Now the gold and silver may have existed in different states pre- 

 ceding the Palaeozoic time. It is to be supposd that these metals 

 would be among the first of the elements to condense on the now solid 

 earth's surface or at least long before the gases which are the constitu- 

 ents of water, had reached a temperature favorable for their combining 

 to form that liquid. Now, then, the water when it condensed on the 

 earth would be at a temperature of ioo° C. This would certainly take 

 in solution alkaline sulphides and carbonates, provided they were 

 present, and we have grounds to believe that they were. This would 

 attack and dissolve any silica or quartz that it came in contact with, and 

 also in turn attack and dissolve gold. Again, were fissures to open into 

 these seas and mineral or rock matter, we may say gold in a molten 

 state to issue therefrom. The gold would be caused to fly into thousands 

 of small particles which would flatten into sheets when coming in 

 contact with solid bodies, failing to do this, into, small spherical bodies. 

 The gold in this state would be more easily attacked by the foregoing 

 solution ; this solution would also dissolve other metals and minerals 

 such as fluor spar and baryta. 



I am not exaggerating when I say that it was possible for free chlorine 

 to be present in large quantities in those waters, this, which is the 

 greatest solvent of gold, would certainly attack all it came in contact 

 with. The principal solvents of silver would be chlorine and sulphur 

 solutions. Or, another theory which may either be taken in conjunction 

 with foregoing or independent of it, is, that these metals may have still 

 remained in the metallic state and have lain under superimposed bodies 

 of rock ; then during hydrothermal activity, the gold, silver, lead and 

 siliceous rocks would become melted ; some of the gold would combine 

 with the silica to form silicate of gold which is a soluble salt, also if a 

 body of sulphur was present, it would combine with the silver, lead 

 and gold to form sulphide. This, then, may have cooled and lain until 

 further subterranean movements caused a fissure to open, or the fissure 

 may have been open during the hydrothermal activity when the fused 

 or liquid masses carried along by aqueous or other vapors would be 

 attracted towards the fissure, as it would be a vacuum compared with the 

 surrounding body of rock and would be deposited on the walls, forming 

 a vein of segregation. 



In support of the foregoing, according to Daubree, Lenormant and 

 others, water under pressure at 204° C. will reduce to a pasty condition 

 almost all ordinary rocks. Daubree has shown that all siliceous rocks in 

 the presence of small quantities of superheated water (say about 10%, 

 which is equal to water of sedimentation), become pasty at 204° C, and 



