Litchfield enquirer., 1854-02-09
BY Dn. HUoAo.

". Watey considered ds q carrier is
 chonging tks su,taee cf tAs easth.
 l Soi.s.
 Their ofice.
 Their composition and ormaiion.
 Irrigation.
 { Bsainage. l,ion.ofgeoloeical fosma,iona
 3 Waler cpms,dercd e aa agen, n the produc-
 The composition of sirs,ifed rocks.
 Mode of their formation.
 Meta norphic rocks
 { The me,eoric agency of water. The agency of riyefe. 1ah@
 VI. Water. the great levellsr of na- ture. sets as a carrier. on | more exten. tensive scale, in changing tue structure of the earth.
 Let us first consider i, in this capa- city as fo,mer of soils.
 q. Eoils perform the following oflicesiin relation to vegetation. ls. they afford the plant aIs,ancl,ofage. 2d, they absorb water, aieand hestto promote ito growth. Sd, they are the work shops in which water and air manufacture this food.
 Soils contain organic substaaces, which chisfy consisls sf decayed yeg,s- tahle smaiier. .rcalled humus. Tie office of hamhs has been stated in the prece- ding pages, but lee ns notice thas its in solebili,y in cold water ensbles 1t to re- main in the soil. otiisrHise long continued rains would dissolse and remove t en- liTely. while they now can cArry it only bg mcchsnical force. When this sub. stance is n,ois tened in the presence of the air iteonre.ss the oxygen of the latter into ca, bonic acid. If the waleri is run. ming 1t will absorb and remove quan. iity of this. and use t perhaps in tccom. posing Torka. as will be shown hereafter. Soils alsO contains inorganic matter, which principally consists of. three in- gredienis; Let. silica in the form Of sand and gsavsl. 2d. alnmnia in the form ol clsy and slaty nasses; and Sd, lime O, ca, honate of lime in ahe foim Of chalk. quick lime. shell sand. or mari, of which one CT more mag haye been arti6cially snpplsd. Thcns iiigrsdieals are gsner> ally ymixsd mechaaicallE. bat i's ahe ease of ciays sl,e siliea and alnmaia which form them are chemically combineL. and can. not he mechanically separated. Subsoi consists of diffsrent material from llse superior earth, although organic matlei lis continually carried into 1t in sinal Qnansiiies by rain. The same carrier slss 1sshep dpRns ahe salts of potash, soda lime. iron and nagnesia. and all soluhl, substances which t meets. and hsaee ss- tablizhea q difference bssseen the tmt soilM Except in the case of porous rOckI 0s like matter beneath, water geneiallj ldeseends kns short dissancs. Wate pEin1asilY converts tho mountain massel into the commitments q soils by freezing i.in iAe crssices of the rocks and crackinl them thunder by ils necessaay sxpsnsios Iris alternate fsetzing anl lhasing grad ually reduces the masses of rOCk and al .Ipws ahe rain water to wash away ths smaller portions. .while the rain iiself ear siapily wears away the solid socks. l Al the hasis of cliffs and mountains parsienlasly. this loose matter cellecis land is nsshsd hy lains into the adjacen valleys. where it gTadnally forms toils Let us in this connection, consider thu general ai,ucfnse of tho eafih's crust Under lhe soil and dsifisd nsaitss. VI geaeFslly fnd solid rDsks Cf two kinds ist. ibess uhieh ara ssafTaneod in layers and whiuh afs aesllsi stfnliGsd. and a thcse which consist of ops unbiolseh mas and are denoniipaaed unssrnlieed. Tn fpEmaF ecnaiat generally q three kindl Icf FgDhsy xiz aanaH1nne, limas1aase ant H1su h.Snea fR.s S.sa~ esass.e..l e...s.s =.