10 president's address. 



salts may be within six or eight inches of the surface. It is there- 

 fore possible in small plots of land to actualh^ remove the whole 

 of these bad salts by removing the surface soil. This could be done 

 by the use of such an implement as a dam scraper. The question 

 may be asked : " Would it be worth while doing this ? " I can 

 only say that many of these alkali spots contain an unusually high 

 percentage of plant food, and if the bad salts are removed the 

 ground should be profusely productive. The presence of large 

 quantities of these salts causes the soil to lose its flaky condition 

 with the result that it forms in the depths of the soil a tough, hard 

 pan, impervious to water and almost impossible to work with pick 

 or plough and renders drainage impossible. I believe that this 

 formation is often styled by farmers in this country " pot-clay," 

 but I fancy that this word " pot-clay " covers several different 

 kinds of hard, impervious sub-soils, the description of which I 

 consider outside the province of this paper. 



I have now finished what I set out to do, viz., to point out " the 

 necessity of applying chemistry to agriculture," but before sitting 

 down I wish to express a hope that the outcome of this annual 

 meeting of the members of this Association may be as beneficial 

 to the steady advancement of Science in South Africa as have been 

 similar gatherings in other years. I also hope that there will be 

 added many names to the list of members of the Society, especially 

 do I desire that it should be so in the case of many young persons 

 who may hereafter become influential persons in the country and 

 who may later on be able to do a great deal to further the study of 

 scientific subiects, and in this way add to the knowledge whichjis 

 so essential if the country and its people are to go ahead on the 

 lines of civilised life and to prosper. 



