Art. XX. — Note on Perforated Rocks from West 

 Australia. 



By E. J. Dunn, F.G.S. 



[Eead 21st October, 1897.] 



In 1893, when at Bayley's Reward Mine, near Coolgardie, 

 the manner in whiel\ a decomposed steatitic rock at the surface 

 was perforated attracted my attention and a specimen was 

 secured. This rock is burrowed and tunnelled through and 

 through in a manner greatly resembling earth tunnelled by 

 worms. Cross sections of these tunnels are circular and about ^ 

 inch in diameter. These perforations were only observed at the 

 surface in an open quarry. 



Early in this year, when visiting the Vale of Coolgardie 

 Mine, seven miles north of Coolgardie, the decomposed granitic 

 rock which here encloses the quartz leefs was found to be much 

 perforated at the surface. Still more remarkable, at the 80 feet 

 level on the underlay of the lode, a face was exposed along the 

 course of a joint parallel to and a few inches from the reef and 

 on the hanging wall ; this face was a network of burrows. Red 

 surface soil was present in all these burrows. At the surface 

 the general mass of the soft granite appears to have been 

 perforated, but at the 80 feet level the tunnels appear to have 

 been contined to one particular joint on the hanging wall of the 

 reef. Possibly this joint permitted the moisture after rains to 

 sink down deeply and these persevering little miners followed in 

 search of water; or else this joint may have been chosen as the 

 easiest ground to mine in. 



From the abundance of the burrows at the 80 feet level, it is 

 highly probable that they may extend quite down to the 100 feet 

 level ; this will be disclosed as mining proceeds. 



Roots of ti-ees (Eucalypts are growing on the surface) follow 

 these burrows to the 80 feet level. In some of the mines tree roots 



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