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THE PROBLEM OF THE LIZA.RD ROCKS. 

 By EDWARD A. WUNSCH, F.G.S. 



At our last Spring meeting I read a short paper on the 

 above subject, and the present communication is intended to 

 form the second part of it. 



The statements in my first paper were almost exclusively of 

 a negative character, consisting of queries and an enumeration 

 of points, all more or less open to question, and I still maintain 

 that no one has as yet succeeded in unravelling the true character 

 of the Lizard rocks. 



And this, not for want of observers, but for want of a 

 theory to include and explain all the facts involved in the investi- 

 gation of this complicated geological district. 



An excellent summary of the opinions of leading geologists 

 has been given in a paper read in March last, to the members 

 of the Plymouth Institution, by my friend, Mr. Howard Eox, 

 and with his kind permission I quote from it the following 

 data : — 



Professor Sedgwick, seventy years ago, as the result of a 

 careful survey of the district, wrote : " We were led to conclude 

 that the great plateau of the Lizard was not composed of 

 stratified rocks." This opinion, being entirely negative, need 

 not be farther discussed. 



Sir Henry de la Beche, fifty years ago, summed up as 

 follows : — 



"As a whole, however, the hornblende and slate rock seems 

 to have formed a basin into which the serpentine and diallage 

 rock seems to have been poured in a state of fusion." With all 

 due respect to this eminent author and splendid surveyor, this 

 theoretical opinion may fairly be relegated to the dark ages of 

 geology, as may also all other opinions and theories which glibly 

 account for everything by a " state of igneous fusiou." 



