GEOLOGY, 



TKAP BOOKS. 

 By F. R. S M I T H. 



TO one who has spent a dozen of years among the 

 cretaceous deposits of Cambridgeshire, visiting, vampire- 

 like, the tombs of the dead — of our ancestral dead! — Dinosaurus, 

 Ichthyosaurus, Plesiosaurus, and their contemporaries ; and pur- 

 loining therefrom, now a spinal column, now a fragmentary skull, 

 and now a caudal appendage, a neighbourhood of bare-faced 

 traps, among which are scattered some beds of presumed non- 

 fossiliferous Old Red Sandstone, must of necessity supply very 

 poor comfort to his old predilections. Such is his reduced state, 

 that he is highly excited, if he find that a boulder has shifted in 

 the river bed, or if he happen on a new species of trap. This latter 

 material has been his great consolation. Bare-faced as is this 

 trap, and uninviting to the palaeontologist, it cannot be said to 

 be wholly without interest. Indeed there are some few points 

 about it, that may afford "fresh fields and pastures new" in the 

 poorest districts. There are always its age, position, structure, 

 composition, &c, and a host of minor facts and appearances 

 upon which the speculative and sanguine mind may theorize 

 and assert with advantage eminently to itself. 



Kinnoull and MoncreirTe hills form a northern limit to a mass 

 of volcanic rocks that extend south to Edinburgh, where they 

 display their features with great dignity. Dupplin is situated 

 on the north end of this trap district, four miles below Perth. 

 A little south of Dupplin Castle is a small felstone quarry, 

 locally called whin-stone, that exhibits the cannon-ball pheno- 

 mena. These balls are of all sizes, and show in their decay 

 concentric lamination. The interstices between the balls are 

 filled with disintegrated trap, in the form of a ferruginous earth. 

 Somewhat less than a mile to the north of the Castle, a cutting 

 has been made through a trap dyke, or rather ridge, that extends 



