\fi ilirrerent cnm;ite?,ari(l unrlcrdifiei'ert circnmstanceF. 

 nFsie power oi" soils to absorb ir.ojsturo. a pririL-ipai os- 

 S'Miria! to their nroc!uctivci)e?s, ought t') be ranch greatop 

 in vvr.j m ami dry countj ies th;uTin cold i^nr! moist ones ; 

 and the qtjjHitity of f. Tie aluminous caith they contairx 

 larger. Soiis likewise, that are situated on flechviiies 

 onghi to be mare absorbent than those in the same cli- 

 rnate on pSa.iis or in vailies*. Tiic prochrclivfMiess of 

 soils ran^t likewise l>e iiifluoiiced by the nature of tha 

 subsoil, or the earthy or stony st: ata on v/hich they rest ; 

 and this c-rcumstance p^u<rtit to be partic.i'^rly atteriiied 

 to, in considering- *:heir chymicai naiure, uud the sysiein 

 oi' impj-ovement. Ti)us. a sandy sci; may sometimes owe 

 its fertility to t'.ie power of the subioil to i-etain waiet ; 

 and an absoibcnt chiyey soil may occasionally be pre- 

 vented from being barren, in a moist camate, by the in-. 

 fiU! nee of a s bstratum (,f saud or gravi-L 

 XVlll. Of thb ciivMicAf. Composition of fertile." 

 Corn Soils in tijis Climate. 

 Those soiis that are m;)sl produ. tive of corn con- 

 tain always certain proportions of ahimmous and calca- 

 reous cai th in a fin.ely divi(h:cl state, and a certain qean- 

 tity of vegetai^ie or animal ma'.ter. 



The quanliiy of calcareous earth is liowr-ver very 

 various, and in some cases e.xeeedingiy small Ave- 

 ry fertile coitj soil from Ormiston in Kast Ijothian ixi- 

 i'ovdcd me, in au hnndi'cd parts, cr.iy eleven pan.s of 

 mild ciiicareous eartii ; it contained twenty iivc [)arts of 

 silicio'is sa!:f!, the Hnclv-ibvided clay amounted to 

 forty-live parts. It lost nine n. decomposed animal and 

 vegetable matter, and four in water, au(J afforded indica- 

 tions of a small quantity of phosphate of lime. 



This soil was of a very line texture, and contained 

 V{ ry few stones or vegetable fibres. It is not unlikely 

 that its fertility was in somi; measure connected with ihe 

 phosohate; i'or tliis substaf.ce is fcund in wheat, oats 

 inid biricy, and may be a part of tiieir food, 



Kfrli»i, Trarvs. WsV Acaimay, to<. V. ji, I'.Tf, 



