On Manures^ ^c. 417 



where whole fields (often their wheat fields) are sowed with them 

 to good advantage. From this impure and mixed mass of cinders, 

 is obtained the marine or mineral^ alkali,^* There are materials suf- 

 ficient in our country, for preparing this substance. Jshes^ of wood, 

 or any vegetable, may be substituted ; to cleanse or recover over 

 dunged grounds. But the ashes are good or bad, according to the 

 greater or less quantity of alkali found in them. It would seem, 

 that ground requires a change o^ manure., as v/ell as oi cro/i. See 

 Vol. II. ^^ 071 plaster of Paris.'* page 46. 



Carbon is the basis of dung. Oil is an ingredient in manure ; 

 and the fattest animals are said to yield the richest, i. e. the most 

 oleaginous, dung. It is probable, that when land has been over- 

 charged with the dung of animals, applied for a succession of years, 

 the residuum has been carbon insoluble in water, (the vehicle of the 

 food of plants,) and perhaps, an overabundance of oils, — which are 

 found in the composition of both plants and animals. The use of 

 alkalies may be, to produce, from the materials deposited in this 

 over-dunged soil, a soap ; which, being soluble in, and miscible 

 with, water, enters into the vessels of plants thereafter cultivated. 

 Thus furnishing, or elaborating, their food, — whatever that may 

 be ; — and thereby giving salutary activity, to an otherwise pernici- 

 ous and unwholesome mass. — See Hoimbifs Dissertation on Lime ; 

 London, 1814, p. 27. 



It is reasonable to believe the allegation,* that soa/ier*s ashes are 

 only valuable for the alkali contained in them. According to the 

 relations of those who have analysed them, in Unc^'land^tht quanti- 

 ty of alkali in a ton of such ashes, never exceeds ten ; and seldom 

 amounts to above four or five pounds. It is evident, then, that the 

 greatest proportion is worse than useless ; because it encumbers 

 the ground, and adds greatly to the expense of applying it. What 

 proportion of alkali may be contained in a ton of our vjood-ashes^ 

 either live or spent, I do not know. R. P. 



The quantity of potash yielded by different vegetables and trees, 

 varies very considerably. A manufacturer at the Saratoga springs, 



* See Appendix. 

 VOL, III. G 3 



