Proceedings, 



xxi 



tioned, however, whether it was not mistaken for decayed vegetable 

 matter, which often resembles peat, but is quite distinct from it. 



Mr. Hodgkinson alluded to the discovery of the chalk formation 

 by the writer, he was, however, of opinion that the geological for- 

 mation of the district would not bear out the existence of chalk in 

 those localities. 



The chairman stated that chalk and other salts, when held in 

 solution, were frequently deposited on evaporation ; and that rich 

 crops of natural crystals were frequently found in caverns. Some- 

 thing of this kind was mentioned in the paper. 



Mr. Blandowski believed that the writer did not furnish suiScIent 

 evidence in proof of his statements concerning the chalk formation 



Dr. Maund suggested that the difference of view might arise 

 from the change by natural causes of limestone, the oxide of cal- 

 cium, into chalk, the carbonate of lime. The lime might have 

 been held in solution as a bicarbonate, and the other equivalent of 

 carbonic acid have been taken up from the air, 



Mr. Blandowski disagreed with the views of Dr. Maund, andsaid 

 that although the chemical composition of lime and chalk is similar, 

 the term chalh could not be applied to all decomposed limestone, 

 and they were different in a geological point of view. 



Clement Hodgkinson, Esq., read a paper ^*On the favourable geo- 

 logical and chemical nature on the principal rocks and soils of Vic- 

 toria, in reference to the production of ordinary cereals and wine." 

 Mr. Hodgkinson, after making some general allusions to the geolo- 

 gical configuration and soils of the other Australian colonies, arrived 

 at the conclusion that soil in general derived from volcanic rocks in 

 Australia was more fertile than that derived from aqueous or plu- 

 tonic rocks. The writer gave an analysis of soil derived from dis- 

 integrated basalt near Melbourne. He !^referred to the important 

 fact, that, near Sydney, there was some land on trap dykes which 

 was under culture and cropped during the past half century, with- 

 out manuring or fallowing, while its fertility remained undiminished. 

 Mr. Hodgkinson attributed this to the intensity of the disintegrat- 

 ing action that has been maintained in the soil, and which action, 

 in his opinion, had set free during the period that the land had been 

 cultivated as large aquantityjof alkalies, phosphates, &c., as had been 

 consumed by the crops. He maintained that soil of this favourable 

 quality occurs in large numbers of isolated patches omong the vol- 

 canic rocks of Victoria. Mr. Hodgkinson next explained the im- 

 portant influence of the inorganic constituents of the soil of the 

 vineyard on the quahty of its wine. He demonstrated that the dis- 

 integration of clayslate was exceedingly favourable for the production 

 of superior wine. He referred to the large quantity of land of this 

 description in the basin of the Yarra, at an easy distance from Mel- 

 bourne, which he stated to be analogous to that of the celebrated 

 vineyards on the schistoze mountains of the Valley of the Rhine. 



