89 



1924. 



After the oat crop of 1923 swedes were to follow. These 

 were put in — June 12th — with 5 cwt. superphosphate and 1 cwt. 

 sulphate of potash per acre, and came a fair plant. The lime 

 plots looked, throughout, somewhat superior to the chalk ones. 

 The roots will be weighed and then fed off on the land by sheep. 



11. RAINFALL AT WOBURN EXPERIMENTAL FARM, 



1923 and 1924. 



(292 ft. above Sea Level.) 



POT-CULTURE EXPERIMENTS, 1923. 



1. The Hills' Experiments, (a) Lead Chloride, (b) Uranium 

 Compounds. 



(a) Lead Chloride. 



In 1922, work with different compounds of lead had shown 

 that, for wheat. 1% of lead as the oxide, carbonate, or sulphate, 

 was not toxic, but that with lead chloride, so soon as .25 per cent, 

 of lead was exceeded, a toxic effect was produced. It was 

 thought well to continue the lead chloride series for a second 

 year. At the same time a fresh series was started, using lead 

 chloride in smaller and intermediate amounts. 



i — Old Series. 



The quantities of lead used in 1922 were .25 per cent., .50 

 per cent., and 1 per cent., as chloride. The soil was from Stack- 

 yard Field, and the salts were mixed with the whole of the soil 



