Good _ham_ may be made of any part of a carcass of mutton, though the leg is preferable; and for this purpose it is cut in the English fashion. It should be rubbed all over with good salt, and a little saltpetre, for ten minutes, and then laid in a dish and covered with a cloth for eight or ten days. After that, it should be slightly rubbed again, for about five minutes, and then hung up in a dry place, say the roof of the kitchen, until used. Wether mutton is used for hams, because it is fat, and it may be cured any time from November to May; but ram-mutton makes the largest and highest-flavored ham, provided it be cured in spring, because it is out of season in autumn. There is an infallible rule for ascertaining the _age_ of mutton by certain marks on the carcass. Observe the color of the breast-bone, when a sheep is dressed--that is, where the breast-bone is separated--which, in a lamb, or before it is one year old, will be quite red; from one to two years old, the upper and lower bone will be changing to white, and a small circle of white will appear round the edges of the other bones, and the middle part of the breast-bone will yet continue red; at three years old, a very small streak of red will be seen in the middle of the four middle bones, and the others will be white; and at four years, all the breast-bone will be of a white or gristly color. CONTRIBUTIONS TO MANUFACTURES. The products of sheep are not merely useful to man; they provide his luxuries as well. The skin of sheep is made into _leather_, and, when so manufactured with the fleece on, makes comfortable mats for the doors of rooms, and rugs for carriages. For this purpose, the best skins are selected, and such as are covered with the longest and most beautiful fleece. _Tanned sheep-skin_ is used in coarse book-binding. _White sheep-skin_, which is not tanned, but so manufactured by a peculiar process, is used as aprons by many classes of workmen, and, in agriculture, as gloves in the harvest; and, when cut into strips, as twine for sewing together the leather coverings and stuffings of horse-collars. _Morocco leather_ is made of sheep-skins, as well as of goat-skins, and the bright red color is given to it by cochineal. _Russia leather_ is also made of sheep-skins, the peculiar odor of which repels insects from its vicinity, and resists the mould arising from damp, the odor being imparted to it in currying, by the empyreumatic oil of the bark of the birch-tree. Besides soft leather, sheep-skins are made into a fine, flexible, thin substance, known by the name of _parchment_; and, though the skins of all animals might be converted into writing materials, only those of the sheep and the she-goat are used for parchment. The finer quality of the substance, called _vellum_, is made of the skins of kids and dead-born lambs; and for its manufacture the town of Strasburgh has long been celebrated.