“This formidable invader is now universally diffused through the whole country, from whence every method has been tried in vain to exterminate it. This species is about nine inches long, of a light-brown colour, mixed with tawny and ash; the throat and belly are of a dirty white, inclining to grey; its feet are naked, and of a pale flesh-colour; the tail is as long as the body, covered with minute dusky scales, thinly interspersed with short hairs. In summer it frequents the banks of rivers, ponds, and ditches, where it lives on frogs, fishes, and small animals. But its rapacity is not entirely confined to these. It destroys rabbits, poultry, young pigeons, &c. It infests the granary, the barn, and the storehouse; does infinite mischief among corn and fruit of all kinds; and not content with satisfying its hunger, frequently carries off large quantities to its hiding-place. It is a bold and fierce little animal, and when closely pursued, will turn and fasten on its assailant. Its bite is keen, and the wound it inflicts is painful and difficult to heal, owing to the form of its teeth, which are long, sharp, and of an irregular shape.
“The rat is amazingly prolific, usually producing from twelve to eighteen young ones at one time. Their numbers would soon increase beyond all power of restraint, were it not for an insatiable appetite, that impels them to destroy and devour each other. The weaker always fall a prey to the stronger; and a large male rat, which usually lives by itself, is dreaded by those of its own species as their most formidable enemy.
“It is a singular fact in the history of those animals, that the skins of such of them as have been devoured in their holes have frequently been found curiously turned inside out, every part being completely inverted, even to the ends of the toes. How the operation is performed it would be difficult to ascertain; but it appears to be effected in some peculiar mode of eating out the contents.
“Besides the numbers that perish in these unnatural conflicts, they have many fierce and inveterate enemies, that take every occasion to destroy them. Mankind have contrived various methods of exterminating these bold intruders. For this purpose traps are often found ineffectual, such being the sagacity of the animals, that when any are drawn into the snare, the others by such means learn to avoid the dangerous allurement, notwithstanding the utmost caution may have been used to conceal the design. The surest method of killing them is by poison. Nux vomica ground and mixed with oatmeal, with a small proportion of oil of rhodium and musk, have been found from experience to be very effectual.
“The water-rat is somewhat smaller than the Norway rat; its head larger and its nose thicker; its eyes are small; its ears short; scarcely appearing through the hair; its teeth are large, strong, and yellow; the hair on its body thicker and longer than that of the common rat, and chiefly of a dark brown colour mixed with red; the belly is grey; the tail five inches long, covered with short black hairs, and the tip with white.
“The water-rat generally frequents the sides of rivers, ponds, and ditches, where it burrows and forms its nest. It feeds on frogs, small fish and spawn, swims and dives remarkably fast, and can continue a long time under water.”[1]
In Mr. Charles Fothergill’s Essay on the Philosophy, Study, and Use of Natural History (1813), we find some reflections which remind us of Ray and Derham. We shall extract a few paragraphs which relate to the subject in hand.
“Nothing can afford a finer illustration of the beautiful order and simplicity of the laws which govern the creation, than the certainty, precision, and regularity with which the natural checks in the superabundant increase of each tribe of animals are managed; and every family is subject to the operation of checks peculiar to the species—whatever it may be—and established by a wise law of the Most High, to counteract the fatal effects that might arise from an ever-active populative principle. It is by the admirable disposition of these checks, the contemplation of which is alone sufficient to astonish the loftiest and most comprehensive soul of man, that the whole system of animal life, in all its various forms, is kept in due strength and equilibrium.
“This subject is worthy of the naturalist’s most serious consideration.”