294 



T. W. E. DAVID. 



water stated to be fathomless. The roots and branches of the 

 tea-trees lying in this water become coated with a soft green 

 vegetable substance, with air bubbles clinging to them. Innumer- 

 able small bubbles of carbon di-oxide are continually rising to the 

 surface of the basin. The water is too hot to bear the hand in 

 for any length of time, but when cooled is good for use and always 

 bright and clear, and free from any taste, while that in the adjoin- 

 ing cold springs is extremely disagreeable. The temperature of 

 the water in two of these hot springs at Mount Browne is 1 20° F. 

 No change has been observed in the hot springs as regards level or 

 temperature. since 1865, when a cattle station was settled there 

 by Mr. Gibson. 



At times the pressure from below forces the thin crust appar- 

 ently of hardened mud upwards, and a flow of thin brown liquid 

 mud spreads about, sometimes in great quantities. In one of the 

 springs at Mount Browne flakes of granite are forced up and lie 

 on the surface. The following is an analysis by Dr. Walter Flight 

 of the white incrustation from these mud springs : — 



Water 27-793 



Silica ... 





... 0-600 



Chlorine 



... 



.. 3-369 



Sodium 



... 



... 2-183 



Carbonic acid 



... 



.. 33-735 



Soda ... 



.. 



... 31-690 



99-370 



Mr. J. E. Carne, f.g.s., informs the Author that he has observed a 

 number of mound springs between Hungerford and Thargomindah. 

 They are composed of hardened grey sandy clay, and attain a 

 height of from fifteen to twenty feet. Their summits are occupied 

 by cup shaped depressions full or partly full of tepid water, in a 

 state of slow movement, so that the water flows sluggishly over 

 the tops of the mounds and accumulates in shallow reedy pools at 

 their base. Numerous gas-bubbles were observed by him coming 

 up through the water in the basins. 



