Geology 



came upon a number of nuggets, the largest of which 

 weighed just over two ounces, the others ranging down 

 to the size of a small pea. In all, from this single cavity, 

 we extracted seventeen ounces of gold. 



Continuing our researches we made numerous other 

 trenches at intervals in the Centre Valley, and every- 

 where came across traces of gold in the sands, though 

 we did not find any more rich gravel pockets. Such 

 doubtless existed beneath the great spreads of sand, 

 but only systematic mining could bring them to light. 

 Before it would be possible to work the sands at a 

 profit it would be necessary to establish proper separat- 

 ing plant, and to adopt hydraulic mining. 



We had still the other two valleys to explore, and 

 here also we might find gold-bearing rocks, as they both 

 appeared to flow from the gneiss mountains. 



For several days past we had noticed a curious- 

 looking grey cloud away on the western horizon, but 

 had been so engrossed in our gold-mining operations 

 that we had paid little attention to it. One evening, 

 while talking over our plans and deciding whether East 

 Valley or West Valley should next claim our attention, 

 we were interrupted by a curious throbbing vibration of 

 the air, hardly as yet a sound, but very disquieting in 

 its effect. 



While we were debating as to its cause it increased 

 until it resembled the muttering of distant thunder, which 

 was later replaced by a sound like the discharge of heavy 

 artillery. This eventually became an almost continuous 

 roar, and at about midnight the western sky became a 

 lurid red, lit up every few seconds by bright flashes of 

 orange yellow light. As we could feel slight tremors of 



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