168 DISTRIBUTION OF BEDDED LEADS 



We know that in the existincr districts there is a marked 

 tendency for leads to narrow, and often to die out altogether, 

 in passing from the plunging nose of the dome back to such 

 distance that the axial line runs horizontally. Conversel}', 

 veins discovered so far back tend to become stronger toward 

 and at the plunge. This principle is applicable to other than 

 distinctly domed regions. An examination of an}- of the anti- 

 clines will show the inquirer that its axis does not run con- 

 stantly horizontally, but undulates, plunging gently now east, 

 now west, for miles at a stretch. In some instances, as the 

 Upper Seal Harbour district, this long plunge is accompanied 

 by belts of leads of proved worth ; but in most sections so far 

 exploited, such leads lie where the plunge is accentuated, fre- 

 quently in both directions, into a partial or complete dome. 

 This does not prove, however, that leads are absent or even rare, 

 in the long plunging stretches of which we have been speaking. 

 It is most probably because of insufficient exploration that we 

 know so few instances like the Upper Seal Harbour district. 

 There are man}- stretches along all the anticlines known to 

 have the long gentle plunge, which may be as likely to have 

 paying belts as the few now worked. Further, the probability 

 of finding distinct domes in parts where they are not now 

 known is very great. Most of the present districts have been 

 discovered by accident, perhaps all ; and none, so far as the 

 author is aware, by deliberate, systematic prospecting, extend- 

 ing over a considerable stretch of country. 



The point in all this is that here is the most promising field 

 for exploration now open to us — the systematic testing of 

 gi'ound for miles along the plunging parts of anticlinal axes. 

 In order to achieve success in this line, the prospecting must be 

 undertaken progressively along the axes of the difierent anti- 

 clines, and must be careful and persistent. It will entail con- 

 siderable expense, for means nuist be employed to reach bed- 

 rock wherever the structural conditions warrant ; but in the 

 end it will undoubtedly repay the company bold enough to 



