69 



tabout by " planetary motion." "We might also point out at 

 the time when the land of Australia was depressed to the 

 •extent of 600 feet below the present sea level our land must 

 have presented a much more diversified insular aspect than 

 now. Moreover, in conjunction with that coincidence, the 

 southern hemisphere being also passing through one of its pro- 

 tracted winters, would lead us to infer a much greater annual 

 rainfall then than we now witness, which in a corresponding 

 ratio would act more extensively to denude and transport to 

 lower situations material building up the once by far more 

 •extensively developed Older Tertiaries. Ample evidence is still 

 presented, from the presence of numerous outliers, of their 

 once general prevalence throughout the uplands of Munno 

 Para and adjoining districts. 



Probable age of the Drift. — As to the question, "What is the 

 probable age of our comparatively recent accumulations ? I 

 am of opinion that they are older than the boulder clays of the 

 northern hemisphere. Xo data have been given to show that 

 sufficient oscillation of the earth has taken place since the era 

 of the Xorthern Drift to warrant a belief that a depression of 

 something like 600 feet so far down as latitude 35 degrees has 

 occured in either hemisphere. Anterior to the period of the 

 northern " boulder clay " we have strong evidence advanced — 

 the Buried River Qlw.nnels of Great Britain and other northern 

 countries — that the land over a great part of that hemisphere 

 stood much higher in relation to the sea than it does at present. 

 Therefore, if the theory upon which my argument is based be 

 correct during the geological epoch immediately preceding the 

 glacial, whilst the land in the northern hemisphere stood higher 

 it accordingly would stand lower in the southern, in all likeli- 

 hood it was during that round of time our so-called Drifts were 

 deposited. 



We might also — I think with some degree of propriety — refer 

 the age of our "Marine Limestone Crust" of Dry Creek 

 Junction and elsewhere throughout the Province as being con- 

 temporaneous with the period of the growth of the now 

 Submarine Forests and Peat-beds of Europe, which Dr. Croll 

 ■considers to have flourished about 22,000 years ago. 



Explanation of Hand Specimens. 

 Xo. 1. Hand specimen of Travertine, or Calc-tuff, from the 

 bed of Smith's Creek, Section 4,160. Substance arranged 

 concentrically around a common centre. Many of the layers, 

 it will be observed, are much denser than others. The darker 

 ones may have derived that hue from an intermixture of the 

 finer particles of dark vegetable mould, caused iutermittently 

 either by the action of winds or flood-waters whilst the concre- 

 tive process of the limy matter was in progress. 



