410 



CHAP. XLVII. 



Sketch towards a Theory of the Earth. 



THOUGH a philosophical geologist will easily collect 

 from this work, nearly all that I can myself state under 

 the present chapter, this would be a task of difficulty to 

 many readers, and, to the mere student, impracticable. 

 To omit such a view, would indeed be a dereliction of 

 duty, as it would be to disappoint reasonable expecta- 

 tion. It is true, that some principal portions of a 

 theory have already been stated, and unavoidably, as 

 general conclusions from facts detailed under this Sys- 

 tem ; insomuch that a restatement of these cannot fail to 

 involve some repetition. But while these do not stand in 

 the order which such a sketch demands, so are there, in 

 the preceding chapters, many subsidiary portions of a 

 theory, of more or less moment, often also but slightly 

 touched on, the bearings and value of which would 

 scarcely be appretiated without the approximation and 

 arrangement here proposed. This then it is equally 

 my object and my duty to do : but it is not all. If there 

 ever is to be a Theory of the Earth, it is not less need- 

 ful to place our present deficiencies in a full light; that 

 the pursuit of this science may no longer be checked, 

 under that contentment which rests in the indolent be- 

 lief that the assertions of bold ignorance are Knowledge. 

 Let our defects be fearlessly and honestly displayed ; 

 and we shall then know what we have yet to learn ; as, 

 then also, may geologists turn their attention to the 

 improvement of this science, to the perfection of that 

 which is the end of all Science, a true Theory, instead 

 of wasting their time on that which can now teach no- 

 thing new, or, still worse, in seeking and perverting 

 facts to support hypotheses. 



