That part of the territory of Michigan, which forms the peninsula lying between the great lakes, is generally level. In its centre, however, is a ridge of table-land about three hundred feet above the lakes, running north and south, and dividing the waters emptying into Erie and Huron from those running to the westward. This peninsula is divided into about equal proportions of grass prairies and forests. Along the southern shore of Lake Michigan is a sandy and barren tract of country, bleak and desolate. But much of the soil of this country is excellent, and its productions are similar to those of the state of New York. The North-West territory has not yet been much explored. That portion of it situated between the Fox and Wisconsin rivers, and the western shore of Lake Michigan, has a rich, black, alluvial soil, and is well watered. The face of the country is unbroken by hills of any magnitude. The most striking feature of the vast Missouri territory is its ocean of prairies. A belt of partially wooded country extends from two to four hundred miles west of the Mississippi and its waters. The immense extent of country west of the two great rivers is generally level, and is covered with grass plains, and sand deserts. On the banks of the streams there is usually a line of rich soil, but as we leave them it becomes barren and dry. Much of this country is as sterile as the deserts of Arabia, though in the most sandy parts there is a thin sward of grass and herbage. The Missouri, the Platte and the Yellow-stone run through a rich soil; but in its upper courses the Arkansas waters only a barren prairie. GENERAL REMARKS ON SOIL. The productiveness of soils is influenced by the nature of the sub-soil, or the earthy or stony strata on which they rest, and this should be attended to in all plans for their improvement. Thus sandy soil may owe its fertility to the power of the sub-soil to retain water; and an absorbent clay soil may occasionally be prevented from being barren by the influence of a substratum of sand and gravel. Those soils that are most productive of corn, contain always certain proportions of aluminous or calcareous earth in a finely divided state, and a certain quantity of vegetable or animal matter. ‘In cases,’ says Sir Humphrey Davy, ‘where a barren soil is examined with a view to its improvement, it ought, in all cases, if possible, to be compared with an extremely fertile soil in the same neighborhood, and in a similar situation; the difference given by their analyses would indicate the methods of cultivation, and thus the plan of improvement would be founded upon accurate scientific principles.