Volcanic Tuff of Pejarh Marsh, 7 



some subterranean passage. As already mentioned the water is 

 fresh, and it would require a considerable access to bring the level 

 up to the gap, which is said to have been reached in the past. 

 There is no doubt that there has been a large diminution in the 

 quantity of water in the lake within recent years, and if this is. 

 caused by the supply, either superficial, or superficial and sub- 

 terranean combined, as the case may be, being exceeded by the 

 loss due to evaporation, it would be noticed in the salinity of the 

 water. Keilambete has also teen lowered in level to some extent 

 during the same time, but the saltness of its waters is very 

 marked. 



A suggestion might here be made Avith regard to this difference 

 in the water of the two lakes which in other respects seem to have 

 much in common. It has been mentioned that in another paper^^ that 

 at Pejark Marsh, in driving a crowbar through the yellow clay, on 

 the top of which cut fragments of bone were found, the bar entered 

 a softer stratum, and water flowed freely from the hole so made, 

 showing that probably the water-bearing bed from which the local 

 residents obtain their supplies, had been tapped. It is also thought 

 that this might be the porous fossiliferous limestone of Tertiary 

 age exposed along the shores of Lake Keilambete for some feet above 

 the present water level. 



On the shores of this lake wells have been sunk for some twenty 

 or thirty feet in the limestone, it is said, and fresh water obtained, 

 although the lake water itself is so saline from the absence of an 

 outlet that it is unfit for consumption by stock. It, therefore, 

 seems evident that the limestone bed is a channel by which the 

 supply of water to Keilambete is augmented to some extent. Now 

 at Lake Terang conditions are apparently different, and the pro- 

 cess is reversed. In this case the water is either being forced out 

 through the porous stratum into the surrounding country, where 

 numerous wells are drawing it away more rapidly than l)efore the 

 stratum was tapped, and more rapidly than it can be naturally 

 replenished, or else underground supplies, which were sufficient to 

 balance the loss by subterranean outlets, have been intercepted. 

 Mahony and Grayson^^ mention this as a probable factor in the 

 desiccation going on at Lake Te'cine:. 



The sides of the lake, or ring of hills enclosing it, are composed 

 principally of bedded tuffs. An extremely good exposure occurs 



16. Spencer and Walcott. "The Origin of Cuts on Bones of Australian Ex- 

 tinct Marsupials." Proc. Roy. Soc. Vict., Pt. I., 1911, p. 93. 



17. Loc. supra cit., p. 10. 



