The thatched roof is torn off by the wind and devoured by mice, the windows are driven in by storms, the walls are soaked through with damp and are crumbling to ruin, the honeysuckle obstructs the entrance which it once adorned, the garden is covered with weeds which years of after-labour will have difficulty to destroy:-- "It was a plot Of garden-ground run wild, its matted weeds Mark'd with the steps of those whom, as they pass'd, The gooseberry-trees that shot in long lank slips, Or currants, hanging from their leafless stems In scanty strings, had tempted to o'erleap The broken wall." Apply this principle upon a large scale. Let the productive energy of a country be suspended through some great cause which prevents its labour continuing in a profitable direction. Let it be overrun by a conqueror, or plundered by domestic tyranny of any kind, so that capital ceases to work with security. The fields suddenly become infertile, the towns lose their inhabitants, the roads grow to be impassable, the canals are choked up, the rivers break down their banks, the sea itself swallows up the land. Shakspere, a great political reasoner as well as a great poet, has described such effects in that part of 'Henry V.' when the Duke of Burgundy exhorts the rival kings to peace:-- "Let it not disgrace me, If I demand, before this royal view, What rub, or what impediment, there is, Why that the naked, poor, and mangled peace, Dear nurse of arts, plenties, and joyful births, Should not, in this best garden of the world, Our fertile France, put up her lovely visage? Alas! she hath from France too long been chas'd; And all her husbandry doth lie on heaps, Corrupting in its own fertility. Her vine, the merry cheerer of the heart, Unpruned, dies; her hedges even-pleach'd, Like prisoners wildly overgrown with hair Put forth disorder'd twigs: her fallow leas, The darnel, hemlock, and rank fumitory Doth root upon; while that the coulter rusts, That should deracinate such savagery: The even mead, that erst brought sweetly forth The freckled cowslip, burnet, and green clover, Wanting the scythe, all uncorrected, rank, Conceives by idleness; and nothing teems But hateful docks, rough thistles, kecksies, burs, Losing both beauty and utility: And as our vineyards, fallows, meads, and hedges, Defective in their natures, grow to wildness; Even so our houses, and ourselves and children, Have lost, or do not learn, for want of time, The sciences that should become our country." [Illustration: Dykes of Holland: destruction by bursting.]