AGRICULTURE WITH CHEMISTRY. 155 



Grains 

 ResicUium of precipitated chalk, - - 480 



Proportion contained therein of fixable air, 212 



Calcareous matter, ----- j^68 



Proportion of vitriolic acid necessary to constitute 

 gypsum with the calcareous matter, - - 354 



Total quantity of gypsum, - - ^ 622. 



SOIL 



