During Post-Miocene Times. 11 



Jas. Geikie in his work, The Great Ice Age, speaks of 

 them as consisting of sheets of " sand, gravel, and wide- 

 spread deposits of clay" (p. 4) ; also, as " a stiff sandy and 

 stony clay, varying in colour and composition, according to 

 the character of the rocks of the district in which it lies. 

 It is full of water- worn stones of all sizes, up to blocks 

 weighing several tons" (A. Geikie's Text Book, p. 161). 



Let us compare these descriptions with the following : — 



Mr. R. H. Stone, mining surveyor, writes as follows of 

 certain deposits in the Ovens : — " The bed-rock is very 

 uneven, consisting principally of soft yellow sandstone with 

 veins of slate intermixed, and occasional bands of hard blue 

 stone (metamorphosed slate). . . . The auriferous drift 

 consists of heavy water-worn gravel and sandstone boulders, 

 slightly intermixed with quartz, and having here and there 

 layers of ironstone cement. In some places there are enormous 

 boulders of bluestone rock, sometimes weighing many tons. 

 The drift is from 3 to 50 feet in depth, and is covered with 

 red loam. . . . Some portions of the drift are very hard 

 and difficult to work, and others so loose as scarcely to 

 require the use of the pick" (B. Smyth's Goldfields, p. 84). 



The following example occurs in the Buninyong Estate 

 Claim, near Ballarat, which is thus described: — ""From No. 

 8 shaft the drive at 410 feet suddenly entered a mixed mass 

 of clay, angular fragments of silurian, from a small size up 

 to several feet in diameter, angular quartz, and dense blocks 

 of exceedingly dense lava, piled one on another, or isolated 

 through the mass. . . . A few isolated nests of gravel 

 were encountered" (Lock's Gold, p. 673). 



Mr. O'Farrell, chairman of the Maryborough Mining 

 Board, reports that on a hill two and a half miles from 

 that town the depth of sinking was from 16 to 24 feet, 

 " through hard cement mixed with large white boulders ;" 

 and also " that at Majorca the sinking was 85 feet, through 

 stiff clay, gravel, and cement. The washdirt was white 

 gravel intermixed with white boulders" (B. Smyth's Gold- 

 fields, pp. 97, 98). Similar examples are so numerous that the 

 only difficulty has been to decide which to select. 



To show how widely this deposit is distributed, I will give 

 three other instances. On the Wimmera, near the edge of 

 the mallee country, the wells pass through marly clay, sand, 

 shells, gravel, and boulders, and then bottom on a rotten 

 granite. At Kiandra, in New South Wales, the sinking shows 

 the following strata: — Surface soil with floating boulders of 



