6a A TREATISE ON THE CONNECTION OF 



a proportion of animal matter for the general uses of ve- 

 getation. The common earth worm, which is inoffensive, 

 may be made to rise to the surface, and to become useful 

 for the domestic purpose of feeding poultry. 



SALINE SUBSTANCES WITH EARTHY BASES. 



Pure clay, chalk or calcareous matter, magnesia, and 

 the earth of iron, are capable of being dissolved by many 

 acids, and of forming salts, which are more or less solu- 

 ble. * 



As some one or more of these salts are contained in 

 most soils, it is an objedt of great importance to agricul- 

 ture, to ascertain what are the combinations which dif- 

 ferent acids make with the earths above-mentioned; 

 which of them are beneficial, and which injurious to ve- 

 getation ; as also how such injurious effc6ls may be cor- 

 refted. 



The 



* Siliceous matter is not included, being soluble only by the fluor acid. 



