Macon.—South-east portion, watered by the Kaskaskia and tributaries; the middle and northern portions by the North Fork of Sangamon, and the north-western part by Salt creek. The prairies large, and in their interior, level and wet,—towards the timber, dry, undulating and rich.

Madison.—The Mississippi lies west; Cahokia and Silver creeks, and Wood river, run through it. A part of this county lies in the American bottom, and is a rich and level alluvion; but much of the county is high, undulating, and proportionably divided into timber and prairie. Well supplied with stone quarries and coal banks.

Macoupen.—The Macoupen creek and branches water its central and western parts, the Cahokia the south-eastern, and the heads of Wood river and Piasau, the south-western parts. A large proportion of the county is excellent soil, well proportioned into timber and prairie, and slightly undulating.

Marion.—Watered by the East Fork, and Crooked creek, tributaries of Kaskaskia river, on its western, and heads of Skillet Fork of Little Wabash on its eastern side. Much of the land of second quality, slightly undulating, about one third timbered,—some of the prairie land level, and inclined to be wet.

McDonough.—Crooked creek and its branches water most of the county. The eastern side, for 8 or 10 miles in width, is prairie,—the western and middle parts suitably divided between prairie and forest land; surface, moderately undulating; soil, very rich.

McLean.—One third of the eastern, and a portion of the northern side, is one vast prairie. The timber is beautifully arranged in groves; the surface moderately undulating, and the soil dry and rich. The head waters of the Sangamon, Mackinau, and the Vermillion of the Illinois, are in this county. Its minerals are quarries of lime and sandstone, and granite bowlders, scattered over the prairies.

Mercer.—Has the Mississippi on the west, and Pope and Edwards rivers interior, along which are fine tracts of timber; in its middle and eastern parts are extensive prairies; surface, generally undulating; soil, rich.

Monroe.—Watered by Horse, Prairie de Long, and Fountain creeks. The American bottom adjacent to the Mississippi is rich alluvion, and divided into timber and prairie. On the bluffs are ravines and sink-holes, with broken land. Further interior is a mixture of timber and prairie. Abundance of limestone, coal, and some copper.

Montgomery.—Watered by Shoal creek and branches, and Hurricane Fork. Surface, high and undulating, and proportionably divided into timber and prairie. Soil, second rate.

Morgan.—A first rate county,—well proportioned into prairie and forest lands,—much of the surface undulating; watered by the Illinois river and Mauvaise-terre, Indian, Plum, Walnut, and Sandy creeks, and heads of Apple creek. Coal, lime and freestone.