252 CHALK AND FLINTS. 



rolled about in -the water till the flints abraded 

 each other into smoothness, and the dust thence 

 produced formed the connecting powder of the 

 gravel. It is impossible to say how long it may 

 have taken to round the nodules and produce the 

 powder : but the period necessary for that, and 

 also for the depositation in the places where it is 

 found, must have been considerable ; and nothing 

 but an action of the sea could have given the sur- 

 face the form which it still has, notwithstanding 

 all the action of art and of the weather. 



But though we could explain by the action 

 of river and estuarial resistance, aided by the 

 winds, all the formation of these alluvial strata, 

 we are not a jot nearer the formation of solid 

 rocks than ever. Nay, when, as we must, we 

 have recourse to the action of the sea, even though 

 that sea had constantly outraged the angry mon- 

 soon at the Cape, or out-eddied the Bay of Biscay, 

 the whole process would be change rather than 

 formation the destruction and breaking down of 

 rocks, and not the consolidation. Even if the chalk 

 is sea- shells, and the flints are sponges, a goodly 

 pressure must have been required to bring them into 

 their present state ; and therefore to seek for their 

 origin, we must examine downwards into the deep. 



What the condition of the sea was, when it 

 covered all the land, for whether, all at the same 

 time or not, the sea must have covered all the 

 land, and covered it to a great depth at some time 

 or other, we cannot say. The mountain limestones 

 would lead us to suppose that it contained shelled 

 animals of some kind or other, long before one 

 foot of the dry land appeared above its surface ; 

 and the Oolites, and many other formations, leave 



