28 DISCUSSION ON THE "lEON BLOW" AT LINDA GOLDFIELD. 



with the high result of assay of one sample of the oxide of 

 iron. In addition, he calls in to explain the presence of this 

 always irregularly distributed metal gold, as I contend, quite 

 unnecessarily, "a more drastic process of origination than 

 simple and quiescent decomposition only," applying this 

 only to the oxide of iron and not to the bulk of the pyrites 

 which fills four-fifths of the same "chasm." 



To return for a moment to the nodules of decomposing 

 pyrites found in the Blow itself, to quote Mr. Thurean again, 

 " these present, neither more or less, former gaseous bubbles 

 surcharged with vaporous sulphuretted solutions of iron 

 becoming rigid when cooled, elongated or rounded by com- 

 pression." This form is almost certainly also due to decomposition 

 which, acting more rapidly on edges and corners of irregular 

 fragments, more or less rounds them off. 



In conclusion, therefore, I maintain that ordinary processes of 

 decomposition are sufiicient to account for all the phenomena 

 presented by the oxide of iron portion of the formation, and 

 that there is no necessity to invoke " a more drastic process of 

 origination strictly speaking volcanic." 



The Seceetaet (Mr. A. Morton), read a letter received 

 from Professor Liversidge, Sydney University, in which he 

 stated that his impression formed upon Mr. Thureau's paper, 

 and without having specimens before him, was that the Iron 

 Blow was not of volcanic origin. It would be almost im- 

 possible to form a decided opinion without actual examination 

 of the Blow. 



