474] RAT they will forsake the situation, if" they cannot hide their upper ave- nue among Aveeds, &c. Dr. Dae- AviN is of opinion, that they may be driven away by keeping the rim or margin round fish-ponds so low, as to rise only two, three, or at most four inches above the level of the water; and also by eradicating high grass and weeds. These ani- mals, however, infest drains, aqne- duiSts, stables, barns, gardens, and houses, as well as rivers ; they swim and dive very dexterously ; commit great depredations on ve- getables, grain, fruits, and even poultry ; nay, they sometimes at- tack and eat living pigs. Consi- derable stores of acorns, beech- mast, and other articles, are often found in their holes, as a provision for tiie winter, during which the males live by themselves, while the females, and young rats sub- sist in barns, out-houses, and simi- lar buildings. Being uncommonly prolific, the water-rat produces from 12 to 19 young at a litter ; and, when un- able to procure food from a parti- cular spot, they rnigrate, in large companies, to towns and villages, ^vhere they disperse themselves in difi'erent dwellings, and devour the c-ommon or house-rat. These crea- tures are so fierce and intrepid, that they will even resist, and bite their pursuers, inflicting dangerous wounds, v-hich are attended with great inflammation, and not easily healed. 2. The ratlus. Black pr Com- mon Rat, is a native of Europe,
- r.d Asia, whence it has been con-
vryed in ships to Africa and Ame- rica. Its head and body are seven irches long ■. the back is of a deep blackish-grcy, and the lower parts ol .an ash-cclour ; the tail is very RAT tliln and scaly, consisting of 250 nngs, and measuring 8 inches in length. These animals have, since the introduftion of the water-rat, considerably decreased in some parts of Europe, and in a few places have entirely been extermi- nated ; but they still abound in Britain, where they continue to multiply ; though different expedi- ents are constantly employed for tlieir extermination. The female is furnished with ten teats, and brings forth several times in the year, from live to six at a Utter. The common rat inhabits barns, granaries, and houses ; in the latter of which it forms nests, between the floors and ceilings, as well as in the vacant spaces between the wainscot and wall. From these recesses, they sally forth in search of food, devouring meat, paper, corn, clothes, poultry, game ; and even gnawing the extremities of in- fants, when asleep : instances have occurred, where these veimin have increased to such an alarming de- gree, that the inhabitants have been compelled to abandon their houses. On account of the extensive da- mage occasioned by both tiitse pre- datory species, various methods of extirpating them are praetiseri, with greater or less success. Dogs, cats, ferrets, and weazels, are their na- tural enemies ; and, though such useful animals destroy great num- bers, yet the killing or taking of rats furnishes employment to many skilful men, who pursue d.tl'erent ways of catching them ; and who are known under the name of Ilai- calcheis. Bats are often caught in traps baited with burnt leatlier, or toast- ed cheese ; but a more ethcacious method of destroying them, ccn^- bists
