266 THOUGHTS IN A GBAVEL-PIT. [xi. 



from the Hind Head ; from what geologists term the 

 greensands, below the chalk. 



And I have a better proof of this at least I should 

 have in every gravel-pit at Eversley in a few pieces 

 of a stone which is not chalk-flint at all ; flattish and 

 oblong, not more than two or three inches in diameter ; 

 of a grayish colour, and a porous worm-eaten surface, 

 which no chalk-flint ever has. They are chert, which 

 abound in the greensand formation ; and insignificant 

 as they look, are a great token of a most important 

 fact ; that the currents which formed our sands and 

 gravels set from the south during a long series of ages, 

 first till they had washed away all the chalk off the 

 Weald, and next till they had washed away a great part 

 of the sands, which then became exposed, the remains 

 whereof form great commons over a wide tract of 

 Surrey. 



Now let me pause, and ask you to observe one 

 thing. How, in inductive science, we arrive, by patient 

 and simple observation of the things around us, at the 

 most grand and surprising results. Of course I am 

 not giving you the whole of the facts which have made 

 this argument certain. I am only giving you enough 

 to make it probable to you. Its certainty has been 

 proved by many different men, labouring in many dif- 

 ferent parts of England, and of the Continent also, 

 and then comparing their discoveries together ; often, 

 of course, making mistakes ; but each working on 

 patiently, and correcting their early mistakes by fresh 

 facts, till they have at last got hold of the true key to 

 the mystery, and are as certain of the existence of the 

 great island of the Weald, and its gradual destruction 

 by the waves and currents of an ancient sea, as if they 



