10 The Hodgkinson Goldfield, Northern Queensland. 



Hawkesbury strata. Thus the upper silurian formation, 

 with its peculiar forms of life, the lower, middle, and upper 

 Devonian, the lower and upper carboniferous strata, are all 

 wanting, with probably others which I do not specify, so as 

 not to define the age of the Hawkesbury beds too closely. 

 All these formations represent distinct animal and vegetable 

 fauna and flora. They may not all of them have been 

 deposited on the slates, but it is extremely probable that 

 some of them were, and to the extent of many thousand 

 feet of rock. They have come and gone, and very few traces 

 of them remain. Slow as the process must have been which 

 removed them, slower still must have been their gradual 

 deposition. Then, again, the Hawkesbury sandstone itself 

 has accumulated to the thickness of at least 2000 feet, and 

 it has left no traces of its former existence except a few 

 outliers, such as Mount Mulligan. We have no evidence 

 here of the changes to which the beds have been subjected 

 during the mesozoic and cainozoic periods, or how much of 

 these rocks may have overlaid them, but that they have 

 been in the place where we find them during that long, 

 untold period of the earth's history. The ranges and the 

 folds of the strata are anterior to the sandstone, and so are 

 the veins, but they are not contemporaneous. The dykes 

 are the last parts of the history of the strata, but they do 

 not penetrate the sandstone. The whole subject of the 

 geological changes evident in Northern Queensland cannot 

 be dealt with in this paper, so I shall not pursue the obvious 

 conclusions suggested by the interesting features of this 

 auriferous region. 



The Hodgkinson Goldfield is estimated to about 600 

 square miles, but probably this is much below the truth. 

 Up to the end of the year 1878 there were 330 reefs proved 

 to be auriferous, and this also must be below the truth, 

 though some of the reefs looked upon as distinct belong to 

 one and the same. It has never been much of an alluvial 

 field. In this respect it offers a remarkable contrast to the 

 Palmer diggings, which has been always richest in alluvial 

 gold. The latter covers an area of about 2000 miles, with 

 only 112 known reefs. The alluvial finds in the field were 

 enormous ; but now that this is beginning to be worked 

 out the population has decreased. The gold reefs on the 

 Hodgkinson are not exceeded in the number of reefs by any 

 field except Charters Towers and the Etheridge and Gilbert, 

 and in the yield of gold it exceeded, in 1878, every field 



