Ch. I.] ITS OBJECTS, AND PLAN. 3 



into the merits of the question on an open and fair field. By 

 thus freely disclosing to my opponents the plan of attack in- 

 tended to be followed in the approaching discussion, my 

 chance of success is certainly not augmented : but truth, not 

 victory, is the object contemplated; and if my conclusions 

 have been legitimately deduced from the facts brought for- 

 ward, their value cannot be diminished by an exposure to the 

 fullest scrutiny. 



It may possibly be regarded as a mark of great presump- 

 tion, in thus venturing to attack opinions which are advocated 

 by the highest authorities : and it can only be urged in ex- 

 tenuation of such a prepossession against my labours, that 

 geology is as yet in its infancy ; and that its pursuit does not, 

 like astronomy, and the more perfect mathematical sciences, 

 require a great depth of learning and acumen in order to 

 enable a zealous disciple to promote its advancement. 



Appealing, therefore, to my long, and I trust not altogether 

 unprofitable, examination of the primary rocks, I rely on the 

 well known candour and liberality of the eminent men from 

 whom I have presumed to differ ; feeling convinced that, if I 

 should substantiate any objection to their theory, they will 

 rejoice that an error has been corrected. 



In conducting the proposed enquiry, there are two objects 

 which will demand attention : First, the description of the 

 primary rocks both of Cornwall and of other countries, in 

 order to ascertain in what respects they are analogous to 

 each other ; and, in the next place, an examination whether 

 the phenomena exhibited by these rocks are in accordance 

 with the principles of the prevailing theory. 



On this plan, the following pages will be nearly equally 

 divided between a narration of facts and hypothetical specu- 

 lations : and the former part will lead to such lengthened 

 preliminary details, as to constitute an essay on primary 

 geology ; which, so far from detracting from the interest of 

 the work, may, perhaps, impart to it a more permanent value 



B 2 



