198 J. B. CLELAND. 



Australia and some of those noticed in hot climates else- 

 where, may be explained by rock-splitting, though perhaps 

 here, in some instances at least, an extensive flat desert- 

 like expanse may take the place, in the production of the 

 phenomenon, of a sheet of water. 



Addendum. — I have received, since writing the above 

 notes, a description of one of these mysterious sounds from 

 Dr. H. J. Parnsworth, of Sydney, He heard it one morn- 

 ing, between 6 and 8 a.m., in a dry and clear atmosphere, 

 about fourteen and a half years ago not very far from the 

 place where I myself also heard it. Dr. Farnsworth says: 

 "I heard a very loud explosion and a rumbling after for 

 some seconds. We, my companions and I, first thought 

 that it was caused by the exploding of one of the mine 

 magazines either at Marble Bar or Bamboo Creek, but 

 decided that neither place stored sufficient powder, etc., 

 to cause such a big noise, and concluded that an earthquake 

 had taken place somewhere not very far off. At the time 

 of the explosion we were travelling between the Ngullagine 

 and Roebourne (a distance of about 400 miles) and were 

 about 100 miles from Ngullagine and 150 miles from the 

 sea. The report seemed to be in a north-easterly direction." 



Mr. E. O. Andrews has also kindly directed my attention 

 to the following reference to the * desert sound ' in ' The 

 Dead Heart of Australia,' (p. 243), by Professor J. W. 

 Gregory, f.r.s. He says: — "The country around Beltana 

 is repeatedly shaken by small earthquake shocks, which, 

 from their nature and distribution, are doubtless caused by 

 slight earth-movements along the fractures that formed 

 Lake Torrens. Farther north, there are fewer earthquake 

 records, but indirect evidence, that earth-movements are 

 still taking place, is afforded by the well known 4 desert 

 sound,' when the stillness of the night is often broken by a 

 deep booming, which appears to rise from below the surface 





