116 MR, W. S. JEVONS : REMARKS 



quantities of the sulphides of iron, arsenic and copper, 

 which are known by the common name of mundic, and 

 are a pretty sure indication that gold is present in a pro- 

 portion highly profitable to the miner. At the same time, 

 these sulphides prove a great obstacle to the process of 

 amalgamation, causing a serious loss both of mercury and 

 of gold. 



The lower parts of the valley are partially filled up with 

 detritus which has evidently been washed down by streams 

 of water from the neighbouring hills. Such detritus con- 

 sists of red and white mottled clays, more or less mixed 

 with sand and gravel, among Avhich quartz pebbles are 

 conspicuous. 



The deposits of gold dust which gave to Bendigo its 

 reputation lie, or rather used to lie, principally in the very 

 lowest strata of the alluvial detritus (technically called by 

 geologists the auriferous drift), but are especially accumu- 

 lated in the deepest channels or hollows worn into the 

 schistose bottom rocks at some former time. Thus, while 

 a large area of ground throughout the valley has proved 

 auriferous, the most valuable claims usually lie in a broad 

 line which does not often coincide with the present Ben- 

 digo Creek, or line of drainage. This line or lead of rich 

 gold deposits has more lately been traced two or three 

 miles below the mouth of the valley, where the present 

 surface of the ground is nearly level. 



Forest Creek, which lies close to the new and con- 

 siderable town of Castlemain, is another large, rich and 

 well known digging. In general nature it so much re- 

 sembles Bendigo that no separate description is necessary ; 

 the schistose ranges, however, are here more bold, and 

 assume a characteristic shape, resembling a very obtuse 

 pyramid. I am not aware that quartz reefs have yet been 

 opened here. 



Creswice's Creek, formerly of high reputation, and a 



