288 



AERATION AND 



Sect. XII. 5 



th 



account in th 



fad 



of 



in Fi 



and 



' e 

 t 



Pruffia, it is direaed to cover the compofl of foil and anim 



ments with a fhed to prevent too great exhalation and ablution 

 Hence though a fummer fallow may be of advantage to a poor foil 

 which has nothing to lofe ; it mull be difadvantageous to a rich ' 

 which has nothing to <r 



D 



Lord Dundonald in his work on the Coiinedion of A^ 



and Chemiftry 



wh 

 oth 



fly fuppofes, that foils beco 



much expofed to the air by fldlowina, from th 

 inflammable matters uniting with oxy 



inj u red , 

 rbon or 



and that then be 



niblned with other materials, they become infoluble, pro 



ducing llmeftone, calcareous nitre, and phofphat of lime 



Butth 



injury to foil by frequent fallowing, which I fufpedl to be 



of 



extenfive, from the efcape of carbonic acid 



mofphere in the form of 



of nitrous acid 



-.*, 



mentioned; or their being wafhed away by 



^^ 



as above 



5 



Hence the great advantages of Mr.TuIFs ingenious difcovery of 



the drill hufbandry are eafily underftood 



rows 



By fowino[ the wh 



depth the gram is neither crowded, nor too thinly difperfed 



2. Nor are the roots buried eith 



low. 





deep in the foil 



week or two 



By turning the foil firft from the row 



d then turning it up ac^alnll: th 



comes newly aerated with all the good effeas in confeq' 

 becomes more penetrable by the fuper£cial roots of the c 



the fecond joint of the corn-ilems, four or fi 



fin 



or too flial- 

 fpring for a 

 the foil be- 

 ence. 4. It 

 )rn. 5. By 



th new flems will flioot 



cond leaf of th 



^.^ 



ted 



ftem : which 



by the caudex of the fe 



contaa with it, as explained in Seft. IX. 3 



now within the foil 



and 7. XVI 



to 



Thus Mr •n.U's „,ethod of heaping foil againft wheat-p LTs up 



tranfplanting th 



> 



fome degree the fame purpofe 



d fettmg them deeper 



in th 



foil 



wi 



much 



■\ 



