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Show • J 188 EMIGRANT'S GUlDE: stratifif!d lime~tone. The slate in various states of compactness, is and of lamina, varying in thickness almost to infinity: it forms the body of t.lw hills in west Pennsylvania ~nd west Virginia, and great part of Obit. The lime tone is found of several very distinct kinds and also resting some places in £trata, and others composed of loose, ~morpbous fragments, imbedded in earth : the former is uy far most abun~ dant. . . In the present im~erfect state of our knowledge respecting the vanou: parts of the ?luo and lilin~is valley, it is impossible to give in de tad, the proportwns of tbe fossil substances that compose the incumbent strata of the country. It m<~y be assumed as a general fact that the sand and 1imestorJe alternate in greater or less proportion: In some places one of those fossiJs preJoruinates in quantity, in others thf'y are found in ne arly equal portions. Kentucky, much of Ten·· lif'SS~e. and part of Ohio, rest upon immense masses of limestone. The rapid_s of ~hio ru~h ~ver a body of this stone. The superstratum at tbe rapids of the Ob10 IS cowpo ed of shell limestone, in which are !een the remains oi testaceous anrrnals often enUre. This stratum is about a foot in thickness, and is follow'ed by common blue limestone. Prec.i pi~es, of more or Jess ~Jevati~n, are found in many places along tlw Oh10 rrver, formed by masse£ of limestone: the most remarkable of thesP. precipices are upon the l'Vest uank near the mouth of the Tennessee river. The Kentucky river and several other streams in that state and Tennessee, flow between enormous waiJs of lime· . stone. In this formation salt springs have been found to a considerable extent. Tbe ~icaceous schist !ormation may be said to prevail N. E. of th_at of hmestone; a_nd, as has already been observed, forms the base ot we~t Pe~l~s!'lvanta, west ~irgi~ia, and the N. E. part of the state of Ohw. l ~Hs lati~r f?rmat10n IS remarkable for the quantity and ex_cellence of tbe b1t_urnmous coal _which it contains; it always contams J?Ore or Jess Jrme!'tone. Hills composed of micaceous schist form_at_JOn, are re~1arkabl~ lor their rounded appearance, and the precJptces_ ~or thetr shelf-hke aspect. This latter effect arises from the more fnaule J)attJre of some of t~e strata than others. Often the unJer stra~um crum~Jes away, and leaves those above jutting out to some considerable dtstance. The banks of the Mononcrehe]a Ale· g~a"!'. an~ their coufiu~nt water.s, afforJ innumerable e~ampl~s, one o_t ~ htch IS near the city of Pittsburg, in the bank of the former nver. Soils forme~ from the decomposition of these various rocks, are gtneral ly fertJie: particularly from Jime~tone. Jn the aspect of the country under review, a consiuera ble diffe· r~nc ~ prevails between the sections S. E. and N. W. of the OhiQ nver. The f(Hmer is much more brol\en than the h1tter and pos· ses s th I · f · · ' · f'. e on Y c lam o mr•tHltallls belongm(T to the whole surface. rt// 1 ~ ret~Jarkal~ le, that tlw riven~ of th.e United States a'l"e but vory ~ e mfiut-Jn ced by tbe Aleghany mountains. A curve line traced f etwee the s~urces of the wc. te1·s, !lowing ir to the Atlantic ocean, · _m~~ those which e ltf'r the Ohio, would c mfot :1nd recro;.:s, tl e minor chaws of the Altg lany. A IJird's ey.e view from New-York to Geor .. :BMIGRANT'5 GUIDE. 18·~ gia, would exhibit the rivers rushing through the gorges of the moun-tains in a great number of places. . . In Potter county in Pennsylvama, IS the extreme east waters of the Ohio, rising about 20 miles N. E .. of the town of Condersport. Setting out from that p1ace and advancmg southwest~ard, the Chestnut ridge forms for one hunJred miles t_he. d~m.arkatwn he tween the eastern and we:3tern streams : but the K1sk1mm•tas branch of the Aleghany, and the Y oughiogheny, Cheat, ancl Tiger valley bran~bes ~f Monongehela, all rise in the Aleghany, properly so called, an~ rn the1r passage pierce the Chestnut ridge. From the sources of T1ger Valley river to the el(treme eastern branches of the great Kenhaway, the diviJing line between the intervening streams would run nearly south, crossing the mountains obliquely. Frotfl the eastern sources of Kenhaway to those of the Frenc~ Broad and Santee the western streams rise in the extreme eastern ndges of the mount;ins, and flow nearly at right angles to th: main chain. By this natural arrangement it is at once percept1ble, _that the S. E. part of the Ohio valley becomes more and mor~ mountamous,T advancing S. Vv. from the north part of Pennsylvama to the N. V\. ext_rernity of Georaia. The Aleghany here, as every where else, cons1sts of long and 0 nearly collateral ridges, frequently cut through by the rivers. Tha intervening valleys are amongst the most agreeable, and, in many instances, most productive parts of t~e Uni!ed State~. Their materials, however, depend upon the rocks from wh1cb those material• are drawn. This is the true reason of the respective comparative fertility of the lands in the northwest and southeast side of the Aleghany mountains. The mere constituent matter of which mountains are composed, can only be interesting to general readers, from the influence that the decomposition of that matter must have upon the adjaceut soil. - The shores of the Atlantic ocean, from Cape Sable to New York, a.nd the bottoms of the Ohio, are both alluvial ; but the latter exceeds the former, in point of fertility, to a great extent. 'I' he Ohio ·~as drawn its supplies of soil frow secondary and transition, whilst t-he border of the Atlantic is from, in most parts, the ruins of primitive lOCKS. The North or Hudson river, the Deleware, and the Susquehanab, are exceptions to the foregoing rule: these three rivers rise on the western secondary, cross the transition and primitive, and carry ·their spoils towards the Atlantic ocean, where they have formed immense borders of alluvion. The Hudson is the only river .of the ·United States, through which the ocean tides are carried over the primitive and transition formations, to the border of the western .secondary; th.is latter circumstance and its exemption from cataracts, ·shoals, or rapids, in its passage from the western secondary to the Atlantic ocean, are the only in~tances where any remarkable features distinguish the geological structure of the Hudson, from the Deleware and Susquehanah rivers. Under the name of this latter stream, are included all the confluent waters of the Chesapeake bay. The Po-tomac is, however, the most southern branch of the Susquehanah, whose sources are in the western secondal'y. James' · river, though |