OCR Text |
Show PHYSICS OF THE SOIL WATE. Finer the Soil Particles Greater thi Number of Pore Spaces .ind Great-er Great-er Amount cf Moiiture. As sell Is rem. .,... , ef Meal .a ei el l"i k It I ' t !!,.,( tli- M,i , 'I' '"! ill) llo! in r ( ; i a' , t,- . 1" the idui:,... n', i ,, .. : '' " "!' ell the ii I",,!'!- Ilio ...,,.r '"" ! .'. II',. I lie ill: el lil o; ''I- "" S"!l "iU ei ;.i,;iii ,,.. n. , ,,; ,,,, he liuinla r ef poi e r . . , ,. ' ,,.. I '' ' '!! I he !' i ;., , . i 1 . . s 1. '!.Hi. I' of ll ,.. C,.i,. n . S I , in Ihe . ' il. .in .:i i, ;,!: .: ' ' h (';,, .(,.. i. it l.nitie'. .. the r . r !: -tin: t T I "'" ' I ."'ii t I- f ' 1 1 el' ilolllllllt "I tt .iter tl V, Ul "a.l,!, I'll! " s p.ici in ... ;s , . wrlel II ' I! I'' pit : Ill fieri llo I,, p. r ,-et.t W!lu. TllS-t I e.ms Ih ,( the 11 i:i hni.l :: :,. . n ; , , , ..nt ef lis '!'" t ttl!'. I'. ,'. , y , r Hio pel" p:iees- ji;,. , upi, H I r ;r,,, M. II I I'll' I' i' 'II if 1 ,' i . s (Lit In. ;,r . and li'ls thr M,a. ; eh .iter. U hni Hie pine spin . i ! tl,.. ,,,i s (,at i lii.ite.l. S.iluii. d . II eai.iinl drain Itself ,, y. Then. II! he ,.ft , ni'oiinil rtery n Ii pa- ;, !,. a thin film , of water wlii. h the jnuif of Kiattta- i lion l annol n niovr his Is know n as 1 li.wliaiM ople water. linn this mols ,' ture the routs of (.hints depend for food and w aler 'apllhny wnin reninted In two j ways; first. ,y the action of plant loots, aecotiil, hy means of cviiporn- ! lion. As the c:i ll'.iiry water from the ! soil ts evaporated the nirfaee tension j of the water tends to approximate the i hoII mirtlclPH until Ly the time ull of the capillary water Is removed the anil partlcleH have been brought within cohesive relationship. This causei the fill to fdirlnk In volume, and tho par tielea beliiR now In-ounht within cose relationship with each the power of cohenloii acm br-tween them. Water readily passes friMi one Mill wan to another. This has been Incorrectly called capillarity. It Is not because capillary tubes are formed In a crushed soil that water Is lost by capillarity. The soil jcralns ilnrliiK the drying process have been no closely approximated to each other that the dry noil grp.lns steal the water wa-ter from the moist ones below and carry It in a stream from one soil , particle to another until It dually reaches the uppermost one. Then It Is carried off into tho air by etuponi- tloll. If a soil that has been subjected lo the dryiiiK and cont rnel lug process be Htlrred with any Implement the soli particles will bn separated so far apart that they will lie beyond cohesive co-hesive ranges of each other. In such a soil It Is almost Impossible for wa tr to travel from one aoll Kraln to another for the power of tlm dust mulch. In Ibis case the water rises by capillarity from tho moist soil below be-low ii n 1 tl It cullies In contact with tho dry, loose and separated particles of the mulch, where It Is diverted from Its upward course. |