256 E. 0. Thiele: 



continuously south-east for about three miles. It descends to the 

 Dolodrook river, which it crosses just above its junction with 

 Thiele's Creek. This stream has been so named by local bush- 

 men, and its name perpetuated by Mr. Dunn. Beyond this 

 junction the serpentine continues on the siouth side of the Dolo- 

 drook for a distance of about one mile, widening out to form 

 a patch of open, park-like ccnmtry, about a quarter of a mile in 

 width, and well covered with good kangaroo grass. Returning to 

 the Monument end, a number of features of interest present 

 themselves. The serpentine in general is much crushed and 

 foliated, and the general strike of the foliation planes is north- 

 west, in conformity with the strike of the slates. Evidence of 

 some shearing and considerable crushing is to be seen through- 

 out the rocks. 



The. schistose edges of the outcropping rocks are prominent in 

 some parts, and project here and there in a characteristic knife- 

 like manner. A small pinnacle about 12 ft. high is kno\^Ti as 

 the Monument, and from its vicinity a grand and imposing view 

 is obtained eastwards to the precipitous cliffs and table top of 

 Welliiigton, and westwards down the deep valley of the Welling- 

 ton river to the rock-ledged summit of the " Crinoline." Last 

 December (1907) the view was rendered particularly striking and 

 charming by a heavy fall of snow, which brought out an infiinite 

 number of rock structures as the snow lay in the crevices and de- 

 pressions on the mountains. 



Several types of serpentine are to be found, partly due to dif- 

 ferent stages in the alteration of the original igneous rock, and 

 also to the character of this rock. A dark green to black, even- 

 grained serpentine with a tendency to a slight mottled character, 

 is fairly oommon. Microscopic sections show that the original 

 rook was rich in olivine, and probably a peridotite. A further 

 stage in oxidation shows a greener base with numerous red spots, 

 forming rather an attractive rock when polished. Such a rock 

 occurs in Roan-Horse Gully. An analysis of the dark variety, by 

 Mr. Ampt, is given : — 



SUKPKNTINK, DOLODUOOK ArKA. 



Silica - - - - 38.43 



Alumina ... 3.08 



Ferric oxide - - - .37 



