Vol. 68.] ANI^I^ERSAKT ABDEESS OF THE PRESIDENT. XCiil 



faced not only the increased expenses of working which result from 

 the greater depths and the consequent higher cost of lifting coal 

 and pumping water, but also the grave danger of serious losses 

 and mistakes. Even though the Commissioners limited their 

 consideration under this heading to the subterranean extension of 

 proved areas, they are justified in their extremely cautious 

 treatment by the variations in structure and character which are 

 practically certain to occur. 



Far greater will be the difficulties which must be associated with 

 those areas, on which the Commission declined to report, areas 

 that may lie concealed beneath the Neozoic cover wholly severed 

 from the exposed fields, and perhaps from each other. In such areas 

 the first charge will be the expense of search and discovery, and, if 

 coal be discovered, there will follow working difficulties at all events 

 not less than those met with in the Commission's unproved fields. 



In the case of all concealed coalfields the existence of an uncon- 

 formable cover not only increases directly the costs of exploration 

 and working, but it very eff'ectively conceals the structure of the 

 rocks beneath. And yet, to mine an area of which the structure is 

 not thoroughly comprehended, is to court loss and perhaps disaster. 

 If even in the exposed fields it has been necessary to ' cut the 

 losses' which arose from imperfect tectonic knowledge, losses 

 which are only too well known to those familiar with coalfields 

 that have been long at work, how much greater will be the risk of 

 loss involved in meeting and overcoming structural difficulties 

 while working blindfolded, as it were, by the baffling cover of newer 

 rock? The only way to minimize this more or less inevitable loss 

 is to find means for investigating the concealed areas as thoroughly 

 as possible before the risk of actual mining operations is embarked 

 upon. And as this can be done at the same time as the search for 

 new coal basins is being prosecuted, there is little excuse for not 

 combining the two operations. 



Such knowledge as we at present possess on the hypogean 

 geology of the area under ISTeozoic rocks, other than that due to 

 general tectonic principles as to the prolongation of structural 

 features from exposed into concealed areas, and from borings carried 

 forward a little in advance of working but not far outside the 

 area of proved fields, has in the majority of cases come from cor- 

 porate or individual expenditure on borings made for various public 

 purposes. Sometimes these bores have been made for exploration, 

 but more usually the commodity sought has been water, salt^ or 

 some substance other than coal. Some of the information thus 



