GEOLOGY. 327 



by denudation ; and the veins of the lower rocks being but the remaining 

 inferior, and therefore less productive, parts of these veins which once cut, 

 both should be surpassed in richness by those of the ripper rocks, which 

 present parts nearer to the original surface. The line of division between 

 the two series of rocks has been given in a former report ; and, according 

 to the theory in question, the more productive veins should be met with 

 rather on the south-east of. the Green Mountain range than within it." 



ON THE DISTRIBUTION OF GOLD. 



The following remarks on the distribution of gold are taken from a re- 

 cent publication of Sir R. G. Murchison : 



" It would ill become any geologist who throws his eye over the gold 

 map of the world prepared by Adolf Erman, to attempt to estimate, at 

 this day, the amount of gold which remains, like that of Australia, unde- 

 tected in the vast regions of the earth, as yet unknown even to geogra- 

 phers, still less to speculate upon the relative proportions of it in such 

 countries. At the same time, the broad features of the case in all known 

 lands may be appealed to, to check extravagant fears and apprehensions 

 respecting an excessive production of the ore. For we can trace the boun- 

 daries, rude as they may be, of a metal ever destined to remain precious 

 on account of those limits in position, breadth and depth by which it is 

 circumscribed in Nature's bank. Let it be borne in mind that "whilst 

 gold has scarcely ever been found, and never in any quantity, in the sec- 

 ondary and tertiary rocks which occupy so large a portion of the surface, 

 mines sunk down into the solid rocks where it does occur have hitherto, 

 with rare exceptions, proved remunerative ; and when they are so, it is 

 only in those cases where the rocks are soft, or the price of labor low. 

 Further : it has been well ascertained, whatever may have been the agency 

 by which this impregnation w r as effected, that the metal has been chiefly 

 accumulated towards the surface of the rocks ; and then, by the abrasion 

 and dispersion of their superficial parts, the richest golden materials have 

 been spread out in limited patches, and generally near the bottom of 

 basin- shaped accumulations of detritus. Now, as every heap of these 

 broken auriferous materials in foreign lands has as well defined a base as 

 each gravel pit of our own country, it is quite certain that hollows so oc- 

 cupied, whether in California or Australia, must be dug out and ex- 

 hausted in a greater or less period. In face, all similar deposits in the old 

 or new world have had their gold abstracted from heaps whose areas 

 have been traced and whose bottoms were reached. Not proceeding be- 

 yond the evidences registered in the stone-book of Nature, it may there- 

 fore be affirmed, that the period of such exhaustion in each country (for 

 the deposits are much shallower in some tracts than in others) will, in 

 great measure, depend on the amount of population and the activity of the 

 workmen in each locality. Anglo-Saxon energy, for example, as applied 

 in California and Australia, may in a few years accomplish results which 



