46 INAUGURAL ADDRESS. 



evidence is that they occupy parallel lines of elevation, having an 

 approximate north and south, bearing, as was first noticed by 

 Jukes*, who remarks, " that to his knowledge there was only one 

 exception in N.W. Australia" ; but the metamorphic area of that 

 region does not offer exceptional features in the strike of its 

 rocks, as over considerable tracts in Arnheim's Land it has been 

 found that the " axes of the ranges coincide with the direction of 

 the strike," which is north and south in the northern part and 

 north-west and south-east in the southern part f , and in the 

 Kimberley district the strike is, according to Hardman |, about 

 W.N.W. to N.W. 



The " primitive schists " and " primitive rocks " of such early 

 observers as Peron, Oxley, Stokes, &c., probably all belong to the 

 Archaean epoch. Of some of them we have actual knowledge, and 

 the existence of crystalline stratified rocks has been made known 

 by subsequent geologists. Strzelecki (1845) was the first to place 

 them in subterposition to the fossiliferous 'strata. Other authors 

 have speculated on their age from structural and lithological 

 considerations. 



Burr, in 1846§, says that "the rocks of which one (Mount 

 Lofty) range is composed are those which belong to the Primary 

 strata, probably corresponding to the Cambrian and Skiddaw 

 systems of Sedgwick," because " they are apparently devoid of the 

 evidence of the existence of animal and vegetable life during their 

 formation." Jukes |1 classed them as metamorphic. 



Tenison Woods, Rev. J. E.^, thought the same rocks "to be 

 probably of either Cambrian or Silurian formation," but went on to 

 say that " this is mere guessw'ork, supported by little more than 

 resemblances in mineral character, &c." 



Selavyn placed the basal parts of the Mount I^ofty chain as the 

 equivalents of Upper Silurian, and higher beds as more resembling 

 the Silurian of the Victorian goldfields.*'* The metamorphic rocks 

 of the Alpine region of Victoria were classed as Lower Silurian, but 

 considering their prevailing strike, N.N.W., their lithological 

 resemblance to those of the Adelaide chain, and the possibility of 

 the altered aspect of the Lower Silurian being due to contact 

 metamorphism, there is presumptive evidence that the main mass 



* Brit. Assoc. Report for 1816-7 ; and Physical Structure of Australia, 1850, p. 79. 



t Tate ; S.A. Pari. Paper, Northern Territory, 1882, p. 2 and map 2. 



i W.A. Pari. Paper, Geology of Kimberley District, 1884. 



I " Remarks Geology S. Aust.," p. 4 (Adelaide). || Phy. Structure. 



H Trans. Phil. Soc, Victoria, 1858, pp. 1C8-176. 



•• S.A. Pari. Paper, Geol. Notes on S. Aust., 1860, pp. 1 and 2. 



