604 Additions and Correftions

ceed from four to fix feet. If irremovable obftacles are in the way which caufe the river to rife higher, the banks muft be higher in proportion. In either cafe, how- exer, the flope of thefe kinds of banks on each fide may be equal to its perpendicular height, and the breadth on the top about one-third of that height; which, fuppofing the bank fix feet high, the bafe would be fourteen feet, and the breadth of the top two feet. See Plate XXXVI. Fig. 5. The materials for making thefe banks fhould be taken as much as poflible from the fides of the river, which will have the double effect of widening the river and forming the embankments; and there fhould bea treneh on the infide(from which materials may alfo be got), with fome fluices, as formerly directed, to drain off any water from within; alfo fluices to let in water from the river, if required, which would very much fertilife the mea~ dows if properly laid out for that purpofe*.”

Farms fituated on the borders of rivers are often liable to injury and incort- venience from them in different ways; as from part of the foil being carried away in times of flood, from the rivers overflowing their banks, and from the rivers in times of flood flowing back into the channels of the rivulets and{treams that con- dud the water from the more elevated and diftant grounds to the rivers, whereby thefe rivulets and ftreams are made alfo to overflow their banks. The danger of the foil‘being‘carried away in time of floods is increafed or decreafed according to cir- cumftances; as the form of the banks, the nature of the foil, the rapidity of the river, and the quantity of the water that lodges on the margins of the banks or falls ‘over them into the river. Where the banks ofa river are perpendicular, if the foil be of a fandy ortich mouldering nature, the danger of part of them being carried away by floods is greater than where they flope‘gently from the farface of the field to the bed of the river, which when they do not they fhould be made fo. But if the foil and fubfoil be an entire mafs of clay or rong loam, and the current of the river do not prefs:more‘upon one part than another, a fabfiantial improvement may be effected by floping the bank fo that the declivity may be one foot in three or four from the furface of the field to the bed of the river. And where gravel mixed with fmall{tones can be conveniently procured, fpreading thefe materials on the floping bank, to the depth of eight or ten inches beyond the flowings of the river, may‘prove‘a good fecurity againft further damage; and if the bank be planted‘thickly with any fort of willow, it will ina fhort time become an impe- netrable fence, and the annual cuttings of woed foon be equal to the value of the

* Beatfon in Communications to the Board of Agriculture, Vol. IT.