This section is from the book "The Balance Of Nature And Modern Conditions Of Cultivation", by George Abbey. Also available from Amazon: The Balance Of Nature And Modern Conditions Of Cultivation.
To the game-preserver the brown rat is very troublesome. It destroys the young birds and the eggs of both pheasants and partridges, and also consumes quantities of grain food. Wary and cunning, rats generally are suspicious of a baited trap, and open trapping is carried on under difficulties. Found most frequently in woods and hedgerows during the summer, they should be extirpated there by ferreting. Good working ferret must be used, not too large, and some smart terriers. The holes must be worked regularly and systematically. Of course, rats in woods and hedgerows may be poisoned, but this way of destroying them is too dangerous to be employed in coverts and rearing grounds. There are other ways of clearing woods and hedgerows of these pests. 1. Placing some oatmeal or barley-meal in small heaps in the places frequented by rats, and this every night until they are found to eat it freely. When it is found that they consume all that is placed for them, get some perfectly fresh plaster of Paris; mix it in a quite dry state in equal proportions with the meal; this mixture should then be substituted for the meal in small heaps as before. If carefully done rats and mice will eat it freely; the plaster sets in the stomach and invariably kills them quickly.
The great advantage of this method is that should foxes, cats, or dogs afterwards eat the rats, no harm will happen to them. 2. "Ratin," a preparation for exterminating rats and mice, and harmless to larger creatures. It causes among rats an epidemic of a particularly fatal nature,often reaching 100 percent. The article must be fresh when laid down, protected from sun, light and rain, and be plentifully distributed. A stronger preparation named Ratinin is available when the weaker kind proves ineffectual. Particulars concerning it can be obtained from the Directors of the Bacteriological Laboratory, 17, Gracechurch Street, London, E.C.