8-8 A TREATISE ON THE CONNECTION OF 



'They are found.in the greatest -quantities in urine ; the 

 good effefts of which, on most soils, being well known, 

 k may be presumed that similar salts to those contained 

 therein must he equally efficacious. 



Phosphoric acid and alkaline salts are contained in the 

 ashes of vegetables ; these salts, or their primary princi- 

 ples, must necessarily have constituted apart of such ve- 

 getables, from which it may be inferred, a priori, that 

 alkaline phosphats are conducive to the growth of plants. 

 Alkaline phosphats are to be obtained by the addition of 

 alkaline carbonats, or mild alkaline salts, to oxygenated 

 peat, or other oxygenated vegetable substances, forming 

 therewith a reddish brown mucilaginous compound. 



OXALAT OF POTASH, OF SODA, AND OF AMMONIAC, 



THESE soluble salts very highly promote vegetation ; 

 and may be had in great abundance by the addition of 

 alkaline salts and other saline matters to oxygenated 

 peat, and also to oxygenated fossile coal, forming there- 

 with 



