The old men say their fathers told them that soon after the fields were left to themselves a change began to be visible. It became green everywhere in the first spring, after London ended, so that all the country looked alike.

The meadows were green, and so was the rising wheat which had been sown, but which neither had nor would receive any further care. Such arable fields as had not been sown, but where the last stubble had been ploughed up, were overrun with couch-grass, and where the short stubble had not been ploughed, the weeds hid it. So that there was no place which was not more or less green; the footpaths were the greenest of all, for such is the nature of grass where it has once been trodden on, and by-and-by, as the summer came on, the former roads were thinly covered with the grass that had spread out from the margin.

In the autumn, as the meadows were not mown, the grass withered as it stood, falling this way and that, as the wind had blown it; the seeds dropped, and the bennets became a greyish-white, or, where the docks and sorrel were thick, a brownish-red. The wheat, after it had ripened, there being no one to reap it, also remained standing, and was eaten by clouds of sparrows, rooks, and pigeons, which flocked to it and were undisturbed, feasting at their pleasure. As the winter came on, the crops were beaten down by the storms, soaked with rain, and trodden upon by herds of animals.

Next summer the prostrate straw of the preceding year was concealed by the young green wheat and barley that sprang up from the grain sown by dropping from the ears, and by quantities of docks, thistles, oxeye daisies, and similar plants. This matted mass grew up through the bleached straw. Charlock, too, hid the rotting roots in the fields under a blaze of yellow flower. The young spring meadow-grass could scarcely push its way up through the long dead grass and bennets of the year previous, but docks and thistles, sorrel, wild carrots, and nettles, found no such difficulty.

Footpaths were concealed by the second year, but roads could be traced, though as green as the sward, and were still the best for walking, because the tangled wheat and weeds, and, in the meadows, the long grass, caught the feet of those who tried to pass through. Year by year the original crops of wheat, barley, oats, and beans asserted their presence by shooting up, but in gradually diminished force, as nettles and coarser plants, such as the wild parsnips, spread out into the fields from the ditches and choked them.

Aquatic grasses from the furrows and water-carriers extended in the meadows, and, with the rushes, helped to destroy or take the place of the former sweet herbage. Meanwhile, the brambles, which grew very fast, had pushed forward their prickly runners farther and farther from the hedges till they had now reached ten or fifteen yards. The briars had followed, and the hedges had widened to three or four times their first breadth, the fields being equally contracted. Starting from all sides at once, these brambles and briars in the course of about twenty years met in the centre of the largest fields.

Hawthorn bushes sprang up among them, and, protected by the briars and thorns from grazing animals, the suckers of elm-trees rose and flourished. Sapling ashes, oaks, sycamores, and horse-chestnuts, lifted their heads. Of old time the cattle would have eaten off the seed leaves with the grass so soon as they were out of the ground, but now most of the acorns that were dropped by birds, and the keys that were wafted by the wind, twirling as they floated, took root and grew into trees. By this time the brambles and briars had choked up and blocked the former roads, which were as impassable as the fields.

No fields, indeed, remained, for where the ground was dry, the thorns, briars, brambles, and saplings already mentioned filled the space, and these thickets and the young trees had converted most part of the country into an immense forest. Where the ground was naturally moist, and the drains had become choked with willow roots, which, when confined in tubes, grow into a mass like the brush of a fox, sedges and flags and rushes covered it. Thorn bushes were there, too, but not so tall; they were hung with lichen. Besides the flags and reeds, vast quantities of the tallest cow-parsnips or "gicks" rose five or six feet high, and the willow herb with its stout stem, almost as woody as a shrub, filled every approach.

By the thirtieth year there was not one single open place, the hills only excepted, where a man could walk, unless he followed the tracks of wild creatures or cut himself a path. The ditches, of course, had long since become full of leaves and dead branches, so that the water which should have run off down them stagnated, and presently spread out into the hollow places and by the corner of what had once been fields, forming marshes where the horsetails, flags, and sedges hid the water.

As no care was taken with the brooks, the hatches upon them gradually rotted, and the force of the winter rains carried away the weak timbers, flooding the lower grounds, which became swamps of larger size. The dams, too, were drilled by water-rats, and the streams percolating through, slowly increased the size of these tunnels till the structure burst, and the current swept on and added to the floods below. Mill-dams stood longer, but, as the ponds silted up, the current flowed round and even through the mill-houses, which, going by degrees to ruin, were in some cases undermined till they fell.

Everywhere the lower lands adjacent to the streams had become marshes, some of them extending for miles in a winding line, and occasionally spreading out to a mile in breadth. This was particularly the case where brooks and streams of some volume joined the rivers, which were also blocked and obstructed in their turn, and the two, overflowing, covered the country around; for the rivers brought down trees and branches, timbers floated from the shore, and all kinds of similar materials, which grounded in the shallows or caught against snags, and formed huge piles where there had been weirs.

Sometimes, after great rains, these piles swept away the timbers of the weir, driven by the irresistible power of the water, and then in its course the flood, carrying the balks before it like battering rams, cracked and split the bridges of solid stone which the ancients had built. These and the iron bridges likewise were overthrown, and presently quite disappeared, for the very foundations were covered with the sand and gravel silted up.

Thus, too, the sites of many villages and towns that anciently existed along the rivers, or on the lower lands adjoining, were concealed by the water and the mud it brought with it. The sedges and reeds that arose completed the work and left nothing visible, so that the mighty buildings of olden days were by these means utterly buried. And, as has been proved by those who have dug for treasures, in our time the very foundations are deep beneath the earth, and not to be got at for the water that oozes into the shafts that they have tried to sink through the sand and mud banks.

From an elevation, therefore, there was nothing visible but endless forest and marsh. On the level ground and plains the view was limited to a short distance, because of the thickets and the saplings which had now become young trees. The downs only were still partially open, yet it was not convenient to walk upon them except in the tracks of animals, because of the long grass which, being no more regularly grazed upon by sheep, as was once the case, grew thick and tangled. Furze, too, and heath covered the slopes, and in places vast quantities of fern. There had always been copses of fir and beech and nut-tree covers, and these increased and spread, while bramble, briar, and hawthorn extended around them.

By degrees the trees of the vale seemed as it were to invade and march up the hills, and, as we see in our time, in many places the downs are hidden altogether with a stunted kind of forest. But all the above happened in the time of the first generation. Besides these things a great physical change took place; but before I speak of that, it will be best to relate what effects were produced upon animals and men.

In the first years after the fields were left to themselves, the fallen and over-ripe corn crops became the resort of innumerable mice. They swarmed to an incredible degree, not only devouring the grain upon the straw that had never been cut, but clearing out every single ear in the wheat-ricks that were standing about the country. Nothing remained in these ricks but straw, pierced with tunnels and runs, the home and breeding-place of mice, which thence poured forth into the fields. Such grain as had been left in barns and granaries, in mills, and in warehouses of the deserted towns, disappeared in the same manner.

When men tried to raise crops in small gardens and enclosures for their sustenance, these legions of mice rushed in and destroyed the produce of their labour. Nothing could keep them out, and if a score were killed, a hundred more supplied their place. These mice were preyed upon by kestrel hawks, owls, and weasels; but at first they made little or no appreciable difference. In a few years, however, the weasels, having such a superabundance of food, trebled in numbers, and in the same way the hawks, owls, and foxes increased. There was then some relief, but even now at intervals districts are invaded, and the granaries and the standing corn suffer from these depredations.

This does not happen every year, but only at intervals, for it is noticed that mice abound very much more in some seasons than others. The extraordinary multiplication of these creatures was the means of providing food for the cats that had been abandoned in the towns, and came forth into the country in droves. Feeding on the mice, they became, in a very short time, quite wild, and their descendants now roam the forest.

In our houses we still have several varieties of the domestic cat, such as the tortoise-shell, which is the most prized, but when the above-mentioned cats became wild, after a while the several varieties disappeared, and left but one wild kind. Those which are now so often seen in the forest, and which do so much mischief about houses and enclosures, are almost all greyish, some being striped, and they are also much longer in the body than the tame. A few are jet black; their skins are then preferred by hunters.

Though the forest cat retires from the sight of man as much as possible, yet it is extremely fierce in defence of its young, and instances have been known where travellers in the woods have been attacked upon unwittingly approaching their dens. Dropping from the boughs of a tree upon the shoulders, the creature flies at the face, inflicting deep scratches and bites, exceedingly painful, and sometimes dangerous, from the tendency to fester. But such cases are rare, and the reason the forest cat is so detested is because it preys upon fowls and poultry, mounting with ease the trees or places where they roost.

Almost worse than the mice were the rats, which came out of the old cities in such vast numbers that the people who survived and saw them are related to have fled in fear. This terror, however, did not last so long as the evil of the mice, for the rats, probably not finding sufficient food when together, scattered abroad, and were destroyed singly by the cats and dogs, who slew them by thousands, far more than they could afterwards eat, so that the carcases were left to decay. It is said that, overcome with hunger, these armies of rats in some cases fell upon each other, and fed on their own kindred. They are still numerous, but do not appear to do the same amount of damage as is occasionally caused by the mice, when the latter invade the cultivated lands.

The dogs, of course, like the cats, were forced by starvation into the fields, where they perished in incredible numbers. Of many species of dogs which are stated to have been plentiful among the ancients, we have now nothing but the name. The poodle is extinct, the Maltese terrier, the Pomeranian, the Italian greyhound, and, it is believed, great numbers of crosses and mongrels have utterly disappeared. There was none to feed them, and they could not find food for themselves, nor could they stand the rigour of the winter when exposed to the frost in the open air.

Some kinds, more hardy and fitted by nature for the chase, became wild, and their descendants are now found in the woods. Of these, there are three sorts which keep apart from each other, and are thought not to interbreed. The most numerous are the black. The black wood-dog is short and stoutly made, with shaggy hair, sometimes marked with white patches.

There can be no doubt that it is the descendant of the ancient sheep-dog, for it is known that the sheep-dog was of that character, and it is said that those who used to keep sheep soon found their dogs abandon the fold, and join the wild troops that fell upon the sheep. The black wood-dogs hunt in packs of ten or more (as many as forty have been counted), and are the pest of the farmer, for, unless his flocks are protected at night within stockades or enclosures, they are certain to be attacked. Not satisfied with killing enough to satisfy hunger, these dogs tear and mangle for sheer delight of blood, and will destroy twenty times as many as they can eat, leaving the miserably torn carcases on the field. Nor are the sheep always safe by day if the wood-dogs happen to be hungry. The shepherd is, therefore, usually accompanied by two or three mastiffs, of whose great size and strength the others stand in awe. At night, and when in large packs, starving in the snow, not even the mastiffs can check them.

No wood-dog, of any kind, has ever been known to attack man, and the hunter in the forest hears their bark in every direction without fear. It is, nevertheless, best to retire out of their way when charging sheep in packs, for they then seem seized with a blind fury, and some who have endeavoured to fight them have been thrown down and seriously mauled. But this has been in the blindness of their rush; no instance has ever been known of their purposely attacking man.

These black wood-dogs will also chase and finally pull down cattle, if they can get within the enclosures, and even horses have fallen victims to their untiring thirst for blood. Not even the wild cattle can always escape, despite their strength, and they have been known to run down stags, though not their usual quarry.

The next kind of wild wood-dog is the yellow, a smaller animal, with smooth hair inclining to a yellow colour, which lives principally upon game, chasing all, from the hare to the stag. It is as swift, or nearly as swift, as the greyhound, and possesses greater endurance. In coursing the hare, it not uncommonly happens that these dogs start from the brake and take the hare, when nearly exhausted, from the hunter's hounds. They will in the same way follow a stag, which has been almost run down by the hunters, and bring him to bay, though in this case they lose their booty, dispersing through fear of man, when the hunters come up in a body.

But such is their love of the chase, that they are known to assemble from their lairs at the distant sound of the horn, and, as the hunters ride through the woods, they often see the yellow dogs flitting along side by side with them through bush and fern. These animals sometimes hunt singly, sometimes in couples, and as the season advances, and winter approaches, in packs of eight or twelve. They never attack sheep or cattle, and avoid man, except when they perceive he is engaged in the chase. There is little doubt that they are the descendants of the dogs which the ancients called lurchers, crossed, perhaps, with the greyhound, and possibly other breeds. When the various species of dogs were thrown on their own resources, those only withstood the exposure and hardships which were naturally hardy, and possessed natural aptitude for the chase.

The third species of wood-dog is the white. They are low on the legs, of a dingy white colour, and much smaller than the other two. They neither attack cattle nor game, though fond of hunting rabbits. This dog is, in fact, a scavenger, living upon the carcases of dead sheep and animals, which are found picked clean in the night. For this purpose it haunts the neighbourhood of habitations, and prowls in the evening over heaps of refuse, scampering away at the least alarm, for it is extremely timid.

It is perfectly harmless, for even the poultry do not dread it, and it will not face a tame cat, if by chance the two meet. It is rarely met with far from habitations, though it will accompany an army on the march. It may be said to remain in one district. The black and yellow dogs, on the contrary, roam about the forest without apparent home. One day the hunter sees signs of their presence, and perhaps may, for a month afterwards, not so much as hear a bark.

This uncertainty in the case of the black dog is the bane of the shepherds; for, not seeing or hearing anything of the enemy for months altogether, in spite of former experience their vigilance relaxes, and suddenly, while they sleep, their flocks are scattered. We still have, among tame dogs, the mastiff, terrier, spaniel, deerhound, and greyhound, all of which are as faithful to man as ever.