AGRICULTURE WITH CHEMISTRY. 201 



the surface may again, for a time, be rendered fertile by 

 the application of alkaline salts and other saline matters : 

 repeated applications would undoubtedly exhaust any 

 soil, and as such these should only be applied alternately 

 with dung or vegetable matters. Every judicious planter 

 keeps a sufficient number of live stock for the purpose 

 of making manure, and sets apart a due proportion of 

 his plantation for producing proper food for their main- 

 tenance. It is necessary that cattle should be kept in great 

 numbers, to provide in some measure for the waste an- 

 nually incurred in the sugar grounds, still there will be a 

 deficiency of manure from the stock so kept, to pre- 

 serve the sugar-cane lands in high condition. 



An idea is here suggested of supplying that deficiency, 

 founded on the principles and facls already mentioned, 

 towards which the following, as it respedls the cultivation 

 of the sugar-cane, is offered as a more full explanation. 



An acre of ground under canes is generally reckoned 

 to produce an hogshead or about twelve cwt. of sugar, 

 besides the molasses, Sec. The tonnage of ships neces- 

 sary to convey such bulky articles to Britain, must be 



c c very 



