East Fork, though not having an equal length of course, drains, however, little if any less surface than does the main branch of White river. The former rises in Hancock and Henry counties, In diana, and including all the confluents, has a general southwestern course of one hundred and fifty miles, draining the counties of Hancock, Henry, Rush, Shelby, Decatur, Jennings, Scott, Bartholomew, Jackson, Lawrence, Orange, Martin, Dubois, with part of Daviess, Monroe, Johnson, Ripley, Jeffer son, Clark, Washington and Pike.
It may be mentioned as a remarkable peculiarity of the valley of White river, that the extreme south eastern source in Jefferson county rises within less than one mile from the right bank of Ohio river, but flowing directly from the latter unites with it as a final recipient one hundred and sixty miles lower down both rivers. A ridge of hills extends over the state of Indiana, from the mouth of Great Miami to that of Wabash, in a southwest by west direction, or very nearly parallel to the opposite course, and at a mean distance of about twenty miles from the channel of Ohio. From this ridge no stream above the size of a large creek enters Ohio, the principal slope being westward into the valley of White river. Below the junction of its two main branches, the channel of' White river in a southwestern direction by comparative courses of thirty miles, separates Knox from Pike and Gibson counties, finally falls into the Wabash nearly op posite to Mount Carmel in Wabash county, Illi nois.
The entire valley of Wabash approaches the form of an ellipsis; the longer axis three hundred miles from the extreme southwestern sources of Little 1Vabash to the northern fountains of Eel river. The greatest breadth two hundred miles from the sources of Graham's Fork, near Madison in Jefferson county, Indiana, to the northwestern fountains of Vermilion river, in the state of Il linois. The whole area of the valley, about forty thousand square miles, exceeding by a small frac tion the one fifth part of the superficies of the whole Ohio valley.
In fixing the relative extent of the confluents of Ohio, Wabash is the third in length of course, and second in regard to area drained; being in the former case exceeded by Tennessee and Cumber land, but in the latter by Tennessee only. As a navigable channel, Wabash is very important. It is but slightly impeded by falls and rapids, and the position of its course could not be more advan tageous if artificially made, to constitute a great link in a chain of intercommunication between the Mississippi basin and lake Erie.
As an agricultural section, it may be doubted whether any other of so great continuous extent, exceeds the Wabash valley. The surface is in part hilly, particularly towards Ohio river; it is no part mountainous, or to any considerable extent a dead level. The northern part exhibits features which evince an advance to the physical section " Prairie;" but the prairies, or natural meadows of Indiana, are of moderate extent when compared with even those of Illinois. Fertility is the general character of the whole soil of the valley.
If peopled only equal to some of the counties of Kentucky, or of Ohio, of not superior soil if taken at a mean, and excluding large towns, the valley of 'Wabash would sustain a population of upwards of four millions.
Geographically this fine portion of theUnited States stretches from north latitude 37° 47' to 41° 30'; and in longitude from 7' 35' to 11° 55' W. from \V. C. The difference of level between the arable extremes is not far above or below one thousand feet; or an equivalent to two and a half degrees of latitude. Adding the result of the difference of level to that of latitude, the extremes of temperature will be six degrees of Fahrenheit. The cultivated soil near the mouth of Wabash is about four hundred feet above the ocean tides, and the highest part say fourteen hundred, the mean elevation of the valley will be from seven hundred to nine hundred feet above the ocean level.