( io6 ) 



EEA OF THE SUPERFICIAL FORMATIONS. 



COMlVrENCEMENT OF PEESENT SrEflES. 



We liave now completed our survey of the series of stra- 

 tified rocks, and ti'aced in their fossils tlie progress of 

 organic creation down to a time whicli seems not long 

 antecedent to tlie appearance of man. There are, never- 

 theless, monuments of still another era or space of time 

 which it is all ])ut certain did also precede that event. 



Over the rock formations of all eras, in various parts 

 of the globe, but confined in general to situations not 

 very elevated. thei*e is a layer of stiff clay, mostly of a 

 blue colour, mingled with fragments of rock of all sizes, 

 travel-worn, and otherwise, and to which geologists give 

 the name of diluviiun, as being apparently the produce of 

 some vast flood, or of the sea thrown into an unusual 

 agitation, it seems to indicate that, at the time when it 

 was laid down, much of the present dry land was under 

 the ocean, a supposition which we shall see supported by 

 other evidence. The included masses of rock have been 

 carefully inspected in many places, and traced to parti- 

 cular parent beds at considerable distances. Connected 

 witli these phenomena are certain rock surfaces on the 

 slopes of hills and elsewhere, which exhil)it groovings and 

 scratchings, such as we might suppose would be pi'oduced 

 by a quantity of loose blocks luiriied along over them by 



