232 



■which are now being analysed in the laboratory of the Mu- 

 seum of Irish Industry, under his direction. He has fully 

 recognised that the chemical composition of a soil will indi- 

 cate its power to supply the materials necessary for the growth 

 of plants, but its practical fertility will depend also on other 

 mechanical and meteoric conditions; and to eliminate these, 

 and to estimate their relative influences, Sir Robert Kane 

 found that it would be highly valuable to contrast, under the 

 form of maps, the chemical constitution of the soils of the 

 several districts, and their relations to climate, with the prac- 

 tical standard of value as given by Mr. Griffith's official valua- 

 tion, the conversion of the numerical estimates of which into 

 a visible and pictorial representation has been the principle of 

 construction of the maps now laid before the Academy. 



Professor Oldham called the attention of the Academy to 

 the importance of connecting the geological structure of a 

 country with all such inquiries as regard the distribution of 

 soils of different value. The county of Wicklow — a soil map 

 of which, coloured from Mr. Griffith's valuation. Sir Robert 

 Kane had exhibited — was one which well illustrated this ; 

 and as the geological map of that county, just published by 

 the Geological Survey, had been presented to the Academy 

 on that evening, a reference to it would shew the very remark- 

 able connexion which existed between the occurrence of cer- 

 tain geological deposits, and the existence of soils of certain 

 values. On this map, /or the first time, the more recent 

 geological deposits — the marls and gravels — of Wicklow, 

 were represented, in addition to the more solid geology of the 

 district. This was accomplished by using for these recent and 

 more superficial deposits an engraved tint, independent of, and 

 in addition to, the conventional colours adopted to represent 

 the different groups of soils. Now, a reference to this map 

 would at once show that all that portion of the map which, 

 on Sir Robert Kane's map, represented by his colours the 



