1\ RELATION TO MIXING POLICY. WOODMAN. i / I 



wliile a very detinite surface lateral extent is known for each 

 true dome, there is many a district in which there are enough 

 paying belts to keep one or a very few large plants for more 

 years than any of us will see. Third, while there is a definite 

 downward limit to each leg of a saddle, at which the vein dies 

 out, it has yet to be shown that any one has reached that limit 

 in a characteristic case. The only vein in this class which has 

 been mined on the slope for a thousand feet of vertical depth 

 shows unchanged character of ore at the bottom. Mr. Fari- 

 bault's contention cannot be too strongly reiterated — that the 

 depth of the vein left for our use depends entirely upon the 

 proportion which erosion to an accidental present level has not 

 removed ; and that this will vary with each vein. Other things 

 being equal, leads nearer the axis of a sharp fold should hold 

 deeper than those farther aw^ay. Yet at Caribou w^e have a 

 vein at a great distance from the axis, operated at over a thousand 

 feet vertically. The advisability of following individual leads to 

 a far greater depth than has been done must be emphasized to the 

 utmost : and if the agitation for vertical sinking, good as it is, 

 has detracted from the interest in this method of working, by so 

 umch it has done an injur}^ to the industry. 



What, then, are the constructive, practical applications which 

 can be made from the facts and principles of the distribution of 

 bedded leads ^ Without attempting to arrange them in any 

 order of relative importance, some of them are as follows : 



( 1 ) There is a great field for exploration for new deposits. 

 This should be systematic, along recognised anticlines for long 

 distances. Special attention should be paid to structures similar 

 to that at Upper Seal Harbour, which are conunon. The 

 conditions of distribution there are in some ways nearer those of 

 Bendigo on a large scale than anywhere else. 



(2) There is room for far more exploring within single 

 districts, but this is preferably done by underground cross-cuts- 



(3) The present districts are even * now held by too many 

 owners for economical workincr. There are few, even of the 



