These courses are sufficient to give a pretty correct idea of the Flemish system of rotation. It will be seen that wheat never succeeds to clover: it almost always follows flax, hemp, cole-seed or potatoes. Clover greatly encourages the growth of dog grass, which, if not completely torn up, with all its roots, the least fibres of the latter which escape, will each produce a new plant, greatly to the prejudice of the wheat. In England the fields are always more or less infected with this pest, while the practice pursued in Flanders completely protects them against it--Wheat is also materially benefited in Flanders, by the repeated digging up, and hoeings, which potatoes require; and by the abundance, and judicious application of manure, spread during the first year of the course. This loses only part of its fertilizing salts, leaving the earth in a high state of fertility, which the Flemish farmer knows well how to augment to the requisite degree without causing the wheat to shed; a circumstance apt to occur, where too great a quantity of manure is used. The following comparative tables, shewing the value which is obtained from one acre in _four_ years, by a farmer, following the Norfolk course, in England, and that obtained, from the same space in _three_ years according to the Flemish course, will best illustrate the superior advantages of the latter over the former: TABLE I.----ENGLAND. 1st. _year_. Turnips, according to Arthur Young, _l._2 4 0 2d. do. Barley, 4 0 0 3d. do. Clover, 3 12 0 4th. do. Wheat, 6 0 0 Wheat Straw, 3 2 6 Barley, do. 0 15 7 ------------- Total produce in 4 years, _l._19 14 1 Giving one year with another, _l._4 18 6-1/4 per acre. TABLE II----FLANDERS. 1st. _year_. Green Oats, _l_. 0 16 8 Potatoes, 10 5 1 2d. do. Wheat, 3 7 8 Spurry, 2 0 1 3d. do. Rye, 2 0 0 Turnips, 2 1 6 Wheat Straw, 1 0 10 Rye do. 1 3 2 Halm, or straw of potatoes, 0 6 2 ------------- Total produce in 3 years, _l._23 7 2 Giving one year with another, _l._7 9 1 per acre.