A GEOLOGICAL HISTORY. 9 



through some rocks upwards of 100 feet, and not 

 find water after all that vast expense, when, if they 

 had gone from 1 to 500 yards from the spot where 

 they commenced, they would surely have got a 

 good supply. It is my opinion, that it is almost an 

 absurdity to commence digging or boring, below 

 the top of any of the primitive rocks, to obtain 

 water of any sufficient quantity, for wherever I 

 have known excavations made in these rocks, the 

 water which filled the cavities had always penetra- 

 ted or wept in, between the Diluvium at top and 

 the main rock, whether it was Granite, Gneiss or 

 any of those which the older Geologists designa- 

 ted as primitive ; and yet there is a small chance 

 that water might be obtained through some un- 

 known hollow fissure, but these cavities appear 

 very rarely in the older rocks. To the miner, as 

 it gives him the dip and the strike of rocks, and 

 may show him when the mine will be flooded, the 

 knowledge of this science, is of the first impor- 

 tance, whether it is intended to mine for coal, the 

 ores of metals, or even in quarrying stone. Many 

 more instances might be adduced, to show the use- 

 fulness of Geology ; but as it expands the mind, 

 being a matter of fact study, this alone, is suffi- 

 cient to recommend it more generally. 

 2 



