12 Evidences of a Glacial Epoch in Victoria 



basalt and large blocks of cement, 7 feet ; clay, 20 feet ; 

 lignite, 18 feet; sand, 3 feet; fine drift, 65 feet; coarse 

 drift, with big boulders of quartz, jasper, and ironstone, and 

 containing gold, 6 feet — total depth, 119 feet (Gold, p. 510). 



At the Field River, in South Australia, there is a deposit 

 of clay and rough blocks of stone piled up indiscriminately 

 (T. P. S., Vol. LXIY.). 



At Gnomery, beyond the Darling, and Fort Burke a well 

 has recently been sunk 192 feet, through sand, clay, and silt. 

 At the depth mentioned a layer of granite boulders and 

 pebbles was encountered. 



These deposits answer closely to the typical till of the Old 

 "World ; but if we examine the great bulk of our alluviums 

 we shall notice in them only a general resemblance. We dis- 

 cover similar materials, but they are more assorted and stra- 

 tified. Our deposits are those of till which has been re- 

 arranged. Massive ice first turned the glacial drift out of its 

 grinding mill ; then melting mountain ice, in torrents, tum- 

 bling from level to level, stripped the till from hill flank and 

 valley side, swept it into the still reaches of the flooded low- 

 lands, and thence carried it out into the shallow sea which 

 occupied all the plains. In these quiet waters the materials 

 were roughly assorted and spread out. In this operation 

 the pre-existing features of the country were completely 

 obliterated by the debris shot upon them. 



Geologists have described similar operations in other 

 countries. James Geikie, in his work, The Great Ice Age, 

 remarks that "the disappearance of a raer de glace was 

 doubtless accompanied by excessive floods ;" and further, that 

 (: we might expect to meet with evidences of such floods in 

 the presence of more or less tumultuous accumulations of 

 gravel, shingle, and boulders. . . . This drift sweeps 

 up and over considerable hills, and occurs on the tops of 

 plateaux and on the dividing ridges of separate river basins. 

 . . . That the drift is not now more continuous is due to 

 subsequent erosion" (pp. 264, 265). 



As an illustration of the water-power set free during the 

 decline of a glacial period, the same author records that, 

 while America was passing through that ordeal, the ice-waters 

 augmented the Mississippi until its average width was 

 seventy-five miles where it is now a bare half-mile broad 

 (id., p. 475, and LyelVs Principles, Yol. I. p., 441). 



To return to our own formations, we must not imagine 

 that when once these leads were buried out of sight they 



