70 Notes on tlie Geology of the Country around Goulburn. 



affords, viz., copper pyrites, galena, blende, stream tin, gold, 

 manganese containing a very small per centage of cobalt and a 

 still smaller one of nickel. Molybdenite also occurs here 

 disseminated in small patches through quartzite, the original 

 component grains of which are easily discernible. Arsenate of 

 iron is also here found, associated with arsenical pyrites. The 

 only ore that I have seen in the quartz porphyry of this county 

 is iron pyrites ; but in a similar rock from other parts of the 

 colony I have seen copper pyrites and also galena. I shall allude 

 to iron ores under the final heading of the subject to which T now 

 proceed. 



SUPEKFICIAL ACCUMULATIONS. 



The scenery of the country, though at first suggestive of past 

 eras of disturbance, is probably attributable to comparatively 

 quiet causes. That the whole mass of the country has been 

 upheaved together to a considerable height above sea level is 

 undeniable ; but there is no probability that the dividing range 

 or any other parts owe their present configuration to the fact of 

 having been lifted up higher than the surrounding masses. 

 Neither is the surface much dependent upon the character of 

 the rocks, for granite is found on the floor of the "Wollondilly 

 Valley, and on one part of the bed of Lake Bathurst ; and 

 granite also forms the higher summits of the dividing range in 

 the south-west. Basalt also occurs in situations both high and 

 low. Still the intricate windings of many creeks and also tie 

 strike of the hills are clearlv traceable to the position of the 

 strata and their mode of disintegration. 



The ravines excavated, in the schistose rocks are generally very 

 steep, and often inaccessible ; but they do not present vertical 

 precipices like the conglomerate of the Gibraltar Bock on the 

 Wollondilly, resembling the chasms in the sandstone upon the 

 Blue Mountains west of Sydney. The present outline of the 

 surface is a sculptured one, the excavating power being running 

 water ; and if any evidence could be adduced of former earth- 

 quakes so as to account for slight alterations in level over large 

 tracts, it would not be difficult to frame a theory of its structure. 

 Throughout the county there is proof of the former action of 

 water at higher levels, and on a comparatively grander scale ; 

 but whether to attribute these appearances to time or to different 

 climatal conditions is, of course, a difficult problem, and belongs 

 rather to the structure of the continent as a whole than to the 

 small portion now under consideration. The section lines 

 exhibiting the inequalities to scale show how comparatively 

 trifling they really are notwithstanding the bold irregularities 

 which they present when viewed in detail. 



The outcrops of strata on the Argyle shore of Lake Q-eorge, 

 which in some cases project in vertical walls above the ground 



