6 ajstniveesaet address. 



eeceyt esploeatiois^s i'n noetheen austealia and 

 Queensland. 



(1.) From these greater events we may now turn to some more 

 recent local discoveries, made in the progress of settlement and 

 development. These are, respectively, on the west and east 

 sides of the Grulf of Carpentaria, in Arnheim's Land, and in the 

 York Peninsula. The former is now familiarly known as the Port 

 Darwin country, a settlement there having been made by South 

 Australia, which now holds it, though widely separated from it. 

 Some of its features are known to ns from the notices in. the 

 public papers and reports respecting its supposed auriferous 

 character ; and long ago I expressed an opinion in print that 

 gold might occur there, judging from the character of the rocks 

 which I had examined. 



The whole of the country forming that part of Arnheim's Land 

 appears to be a trough resting on granite as a base, which is 

 flanked by slates supporting sandstones, and Tertiary deposits 

 still younger. The general strike of these formations appears to 

 be IST.E. or N.N.E. Melville Island is an outlier of the granitic 

 formation, with littoral deposits of white clay and red sandstone, 

 such as occur from Port Essington round Van Diemen's GTulf to 

 Cape Hotham on its southern border. Granite again occurs S.E. 

 of Port Darwin and on the Alligator Eiver. 



A similar strike of the rocks appears to mark the line of 

 country from the "Victoria Eiver of Grregory to Caledon, Arnheim, 

 and Melville Bays, at the northern and north-western corner of 

 the G-ulf of Carpentaria, where granite again occurs, the slates 

 following the same trend. There is, no doubt, a large area of 

 country in many respects resembling the auriferous regions else- 

 where. 



From Leichhardt's description of the massive plateau along the 

 Alligator, it would appear to have much in common with the 

 great sandstone tracts in New South "Wales. But in absence of 

 any fossil evidence (for the data of that kind collected by Leich- 

 hardt he was compelled to abandon), the exact age can hardly be 



