22 T. S. Will: 



flanks of Tower Hill, as the railway runs d()\\^l through cuttings 

 towards Warrnanibool, well stratified tuflEs are extensively dis- 

 played. There is a similar well bedded tuff, though only a few 

 feet in thickness, overlying the Kalininan a-t "McDonald's" on 

 Muddy Creek, near Hamilton. Quite recently I have seen many 

 square miles of equally well bedded tuffs about Mount Gambler 

 in the south-east corner of South Australia, and to these atten- 

 tion will be more fully directed later. 



Similar, though usually obscure, bedding is shown in the 

 scoria on the Hanks of Mount Leurai. The great banks have 

 been extensively worked for many years for railway ballast and 

 for covering footpaths, so that ever changing sections were 

 displayed. 



Though bedding appears extremely common in the tuffs, it is 

 not universal, and I call to mind a section shown in a road cut- 

 ting near the Park gates at Camperdown where bedded tuffs 

 show a faulted contact with unstratified ones. 



The bedding is generally of such a well marked character that 

 rough flags can be quaa'ried almost everywhere. 



The question arises, To what is this bedding due I Was the 

 deposition subaqueous or merely subaerial? Till recently 1 

 never thought of the possibility of anything but subaerial de- 

 position being suggested in most of the places mentioned. Pro- 

 fessor J. W. Gregory^ holds that the beds round Camperdown 

 are of subaqueous origin, and that the stratification is due to 

 sorting by water. Of the correctness of this view I have doubts, 

 and I have lately found evidence at Mount Gambler w^hich shows 

 that well bedded tuft's may owe their stratification to subaerial 

 sorting, and hence no reason exists for calling on large lakes 

 or the sea to explain their character. 



Tte assertion of subaqueous deposition for all these tuff's would 

 demand the existence of large bodies of water, either marine or 

 fresh water, extending over very wide areas and at various 

 periods. The well-bedded tufl's of Ciu'lewis and Airey's Inlet 

 are older tertiary age. Those of K(u-odt, Muddy Creek and 

 Mount Gambler are recent. The BuUenmerri tuff's may be 

 pleistocene. The supposed subaqueous deposition of the tuff's of 



1 Geojjfi-aphy of \icloiia, p. 128. 



