BY PROFESSOR STEPHENS. 525 



to the East of the fault. This would by slow degrees leave the 

 left bank as a steep slope overhanging the river, capped with the 

 oldest shingle, and stepped by the latter and lower drift in shelves 

 as described ; until at last the downward movement of the 

 seaward side was arrested, and the bottom conglomerate began to 

 be formed. It would seem that at this period the landscape east 

 of the Orara range was something like what it is now, a somewhat 

 rugged but undulating surface extending to the sea, with its coast 

 ranges more elevated than those inland ; but that it differed from the 

 present in being formed of slates, of less hardness perhaps, and less 

 vertical, but still of no other formation than those to the westward. 

 The sliding movement of one side of the fault againstthe other gradu- 

 ally ceased, eased possibly by the formation of a parallel fault or set of 

 faults near or beyond the sea margin. The existence of this second 

 fault is supported by much probable evidence drawn from the 

 character of the coast, and the eastward limitation of the Clarence 

 Basin. Without at present entering into details I should refer, as 

 an illustration, to the double line of fault which almost certainly 

 exists in the Waianamata District, but affecting the older rocks 

 only ; one line along, or a little to the west of, the channel of the 

 Nepean ; the other, some distance to the East of the Coast. The 

 first is partially masked by the overlying Hawkesbury sandstone ; 

 the second concealed by the sea. 



At any rate there must have been such a cessation of opposite 

 movements as I have described. For thereafter we can trace 

 no elevation of the one side concurrent with subsidence of the 

 other, but both portions move together, whether upwards or 

 downwards. 



And so, after an indefinite period of rest, (or perhaps of rising) 

 the whole district began again to subside. Great lakes were 

 gradually formed and great rivers still carrying down the debris 

 of the wasting continent, filled up the hollows with beds of sand 

 or mud, interspersed with drifted logs and the vegetation from 

 their banks. 



The ancient surface sank the faster under this accumulation, 

 which by degrees obliterated every salient feature, burying all 



