152 



OUTLIEES. 



it might be instituted with any probability of success. It 

 has been observed with reference to such a question, that 

 if the dip of the strata in the vicinity be towards the estate 

 where the trial is to be made, it is probable that the coal 

 may be found under it ; but if the dip is in a contrary direc- 

 tion, the search ought not to be undertaken. The accom- 

 panying figure will explain the reason. 



FIG. 



The beds 1, 2, 3, and 4, are a series of coal-strata dipping 

 towards d; the un conformable strata, c c, are beds of sand- 

 stone lying over the coal. Supposing, the coal-vein 4 rises 

 to the surface at that point on the estate of A, adjoining the 

 estate of B, which lies towards d, it is then apparent that A 

 would find only a point of the vein on his estate, and that it 

 would be useless to search in the direction of b for coal, since 

 the dip of 4 is sufficient to prove that none exists there. But 

 on the estate of B, though no coal came to the surface, still 

 the dip of that which exists on the estate of A would render 

 it highly probable that coal would be found ; the possibility 

 of the coal lying too deep for working, &c., being considera- 

 tions which would depend on the angle of dip, and other 

 circumstances of local character. 



FIG. 90. 



OUTLIEES. Strata are said to form outliers, when they 

 constitute an isolated portion detached from the principal 



