298 BOARD OF AGRICULTURE. 



throughout. The cost of tlie phosphoric acid varies grcatl}', how- 

 ever, ill tlic three cases, that furnished by the ground S. C. rock cost- 

 inir not over a third of the market value of the same amount in the 

 other two forms. 



The following table gives the kinds and quantities of fertilizers 

 used, and the yields of grain and straw on each plot. 



The crop grown was oats. The seed was sown May loth, and the 

 crop was cut August 13th. 



This experiment involves the first series of eighteen plots. 



