This section is from the book "Preserving And Pickling", by Mary M. Wright. Also available from Amazon: Preserving and Pickling: Two Hundred Recipes for Preserves, Jellies, Jams, Marmalades, Pickles, Relishes and Other Good Things.
Small pears should be pickled whole, while the large ones should be halved and cored, and all should be peeled. Use to each five pounds of pears two pounds of sugar, one quart of water, one pint of good vinegar, one teaspoonful each of cloves, cinnamon and allspice, and one tablespoonful of ginger root. If you wish these a little stronger with vinegar, use one quart of vinegar and one pint of water. When the syrup has come to the boiling point, put the fruit in and simmer slowly until tender, then fill carefully into jars, pour the hot syrup over them, and seal.