AMERICAN INSTITUTE. 44T 



required and the long delay have not allowed this method to he practised. 

 The roasting of the ore, which is usually resorted to, deprives the pyrites of 

 only one of its two equivalents of sulphur, the proto-sulphuret then fuses 

 without decomposition. 



When the gold is mixed in the metallic form with quartz or other earthy 

 minerals the mechAnical processes of crushing often bring portions of the 

 gold to the form of gold leaf, in which state the metal floats on water. It 

 is thus rendered difficult of amalgamation, and if not amalgamated is swept 

 away when the mass is washed. 



The only known instance in which no gold has heen lost, is said to be in 

 Russia. The gold is there disseminated through an ore of peroxide of iron. 

 The ore is treated in a blast furnace exactly as in the manufacture of cast 

 iron. The pigs which result are treated with dilute sulphuric acid. 



Professor Hedrick called attention to the fact that there are well marked 

 forms of pyrites which contain gold. Also that the problem for the metal' 

 lurgist is to remove all impurities, sulphur &c., from the gold. 



Mr. Seeley had gained much knowledge from the remarks already made. 

 He could not find similar information in books. He would suggest that 

 an alkaline sulphuret of silver is very difficult to remove from combination 

 with gold. 



Dr. Stevens stated that he found gold distributed throughout the soil in 

 Illinois. Where did it come from ? All the soil is derived from the 

 higher land, from the hill country. It is therefore certain that the hills 

 which furnished the soil, contain gold. 



There have been no veins found south of Lake Superior. Some veins 

 may exist to the north of it. His conviction is that there is at the north- 

 west, and long before we reach the Sierra Nevada gold region, strata of au- 

 riferous rocks or original deposits. The soil of all the western states, 

 yields more or less gold, whether taken at the surface or at a depth of five 

 hundred feet. In some localities it may be discovered at the surface, while 

 in other places traces of gold are found only at some depth. In Iowa and 

 Illinois, plate gold, exceedingly thin, has been found. 



We have more correct information on the gold found in California, than 

 on any found in other localities. Dr. Trask, a practical man, whose 

 information is reliable, says that the gold of California is found in three 

 distinct veins. The first trends north and south, and if any iron is asso- 

 ciated with this gold, it is a magnetic sulphuret of iron and not iron pyrites. 

 The second trends N. W. and S. E., and crosses the other one. This is 

 associated with pyritical silver, copper, and other metals. The third vein 

 occurs in the system of upheaved tertiary rocks. It trends east and west, 

 and crosses the other two ; and is richly associated with other metals and 

 with sulphurets. These three deposits are well established and distinctly 

 recognized. 



Professor Hedrick stated that, in Morth Carolina, the gold veins trend 

 N. E. and S. W. 



Dr. Vanderweyde said, " it is a remarkable and important fact that all 



