154 



LESSONS IN CHOnSTRT. 



discovered in the ashes of plants, and the table given at p. 99, 

 will show you the proportions in which the crops that you 

 cultivate require them for their growth. Though the success 

 of the experiments which have been made with various saline 

 compounds, both in England and Scotland, are most encou- 

 raging, yet in the present circumstances of the agriculture of 

 this country, with rich stores of fertilizing materials acces- 

 sible to every farmer, your attention should be directed 

 rather to the economy of the natm-al supplies of these matters, 

 which have lately been described, than to the preparations of 

 the chemical manufacturer. The following table, however, 

 will be found useful to those who possess the means, and are 

 desirous of entering upon this new path, which the progress 

 recently made in the study of the composition of the 

 inorganic matter of plants, has opened up to the improving 

 agriculturist. 



Composition in 100 parts of the saline and mineral substances 

 employed in the preparation of special manures. 



Carbonate of Potash 

 Carbonate of Soda, 



dry 



CrystaUized 



Sulphate of Soda ) 

 Glauber Salt, dry j 



CrystaUized 



Nitrate of Potash 1 



Saltpetre > 



Nitrate of Sodaj 



Cubic Nitre J "' 

 Carbonate of Lime . 

 Sulphate of Do. ^ 

 Gypsum, Crystal- > 



lized J 



B urned 



Carbonate of Mag- 

 nesia 



Sulphate of Do. j 

 Epsom Salt . . . j 



31-43 



15-43 



43-71 



51-69 



* Nitric acid is the " aquafortis " of the apothecary. It is a sour 

 corrosive liquid, -which, in combination with potash, forms the salt 

 termed nitrate of potash, and -with soda, nitrate of soda. It is itself not 

 an elementary body like chlorine (51), but a compound of nitrogen and 

 oxygen — 141bs» of nitrogen and 40 lbs. of oxygen forming 54 lbs. uf 



