Of a Country on the Climate. 



211 



proceed to consider in what manner geological formations 

 may take the place of other physical characters in modifying 

 a climate. These act, either by storing water in svibterranean 

 lakes, and in loose sandy strata, or by permitting the storm 

 waters to flow rapidly and at once to the river basins, and 

 thence to the sea. Under the former of these conditions we 

 have permanent and abundant springs and well filled river 

 basins ; under the latter, feeble springs, generally arid sum- 

 mers, and a deficiency of river currents. 



In this case I shall confine my illustrations as much as 

 possible to Victoria ; but, in attributing all due importance 

 to geological structure, we must not forget that it is only one 

 of the causes formerly adverted to — not the most important 

 in the extent of its results — and chiefly worthy of especial 

 notice, because it immediately concerns man in his daily 

 wants and pursuits. 



It is necessary for me to refer you again to section No, 1, 

 which very fairly exhibits the geology of the greater part of 

 Victoria. It will be seen on reference thereto how the rivers 

 of this country are supplied with water. 



The paleozoic rocks upheaved by the granite are highly 

 inclined or vertical. The newer tertiary formations, and 

 alluvium constantly occur. These are shown in the section, 

 reposing in the valleys, forming the beds of numerous creeks, 

 and separated by steep narrow ranges of clay slate and 

 sandstone. 



It is manifest that the storm waters, received on a surface 

 of this kind, must be quickly conveyed to the river beds, since 

 the higher lands are almost destitute of soil. I have seen 

 miles of schistose rocks and granite, where the tops and sides 

 of the ridges presented at every turn the outcrop of the rocks. 



The numerous guUeys are, however, almost Invariably 

 covered with a thin stratum of porous sandy clay and gravel, 

 with a pretty strong clay substratum. 



Even if the ridges of paleozoic rocks were less steep, and 

 better clad with soil, it is evident if they absorbed much of 

 the rainfall, that it would be conveyed to great depths 

 beneath the surface, and could not again appear as springs 

 except under very peculiar circumstances. 



The granite rocks may retain small supplies of water, which 

 slowly percolating through the close seams of such a rock, 

 will reappear in small patches of swamp or in springs, but 

 these latter are seldom found of large volume. 



Streams of water which are seen to issue from granite 

 rocks, are usually traceable to some SAvamp or morass in the 



