The Book of Household Management by Mrs. Beeton

knows how prone he is to disease, how that disease injures the quality of the meat, and how eagerly he pounces on a bit of coal or cinder, or any coarse dry substance that will adulterate the rich food on which he lives, and by affording soda to his system, correct the vitiated fluids of his body,--yet very few have the judgment to act on what they see, and by supplying the pig with a few shovelfuls of cinders in his sty, save the necessity of his rooting for what is so needful to his health. Instead of this, however, and without supplying the animal with what its instinct craves for, his nostril is bored with a red-hot iron, and a ring clinched in his nose to prevent rooting for what he feels to be absolutely necessary for his health; and ignoring the fact that, in a domestic state at least, the pig lives on the richest of all food,--scraps of cooked animal substances, boiled vegetables, bread, and other items, given in that concentrated essence of aliment for a quadruped called wash, and that he eats to repletion, takes no exercise, and finally sleeps all the twenty-four hours he is not eating, and then, when the animal at last seeks for those medicinal aids which would obviate the evil of such a forcing diet, his keeper, instead of meeting his animal instinct by human reason, and giving him what he seeks, has the inhumanity to torture him by a ring, that, keeping up a perpetual "raw" in the pig's snout, prevents his digging for those corrective drugs which would remove the evils of his artificial existence.