tribe. The stalks of erect plants fall when they ripen, and thus the seed reaches the ground at a distance from the roots which produced them. There seems, indeed, to be generally a disposition in the earth to require changes in the plants it nourishes, in order that it may impart the food that is best adapted for each; and Providence, in his infinite wisdom, has endowed these while growing in a state of nature, with such properties as are best calculated to effect the changes. Let the cultivator, therefore, study nature, and follow her dictates, if he wishes either success or applause in his employment. In regard to changes of crops, a general rule has been recommended of alternate growths of leguminous and culmiferous kinds, and of green crops and grain crops; but perhaps it would be quite as philosophical to insist upon alternate growths of fibrous, and tap-rooted plants; the former deriving their food from the surface of the earth, the latter from greater depths. But the value of crops, and the expense of raising each, should be duly estimated in making selections for rotations. Let us say, for instance, that the average crops of wheat, barley, and Indian corn, at their greatest extent, may average 50 dollars in value to the acre, after the grain is ready for market; crops of rye, oats and peas, not more than two thirds of this amount; buck-wheat, considerably less. From lands suitable for ruta baga, or mangel wurzel, it would seem that from five to six hundred bushels to the acre may be expected with good culture; which at 18 cents per bushel, a price certainly not beyond the proportionate value we have just given to the grain crops, will average about a hundred dollars to the value of an acre. The entire expense of either of these crops of roots, when ready for use, is not essentially greater than the expense incurred in producing grain crops; of course, it must be evident that these afford from 30 to 50 dollars an acre less of clear profit than a crop of either of the roots first mentioned. With a proper application of the requisite quantity of manure to ruta baga, it may be successfully grown on almost any dry soil, when well and deeply mellowed, from the sandy to the deep rich loams. Soils of the latter description are best adapted for mangle wurzel. Either of these roots, when steam boiled, and especially with the addition of some meal, will answer all the purposes for which grain is used for feeding cattle of all sorts, from the horse down to the hog. Even stage horses, which, from the severity of their labour, require the most nourishing food, have been kept in England on hay and steam-boiled ruta baga. Mr. Cobbett says, "a hog of a good sort may be sufficiently fatted with this root when steam-boiled." Allowing, what we believe can hardly be admitted, that a bushel of oats contains as much nutriment as three of this root, still it is evident that the usual product of one acre of it will go as far in keeping horses as four of oats.