Tin, or Stannum, one of the imperfect metals, which is obtained principally from the county of Cornwall, where it is sometimes dug up in a native or pure state ; though more frequently mixed with a large portion of arsenic, sulphur, and iron. The crude ore is first broken to pieces, and washed ; then roasted in an intense heat, which dissipates the arsenic; and afterwards fused in a furnace, till it be reduced to a metallic state.

Tin is the lightest and most fusible of all metals : it is of a greyish-white colour; has a strong, disagreeable taste; and, when rubbed, emits a peculiar odour. it is also remarkably malleable ; and, when beaten into very thin plates, or tinfoil, is employed in covering LOOKING-GLASSES. Farther, tin readily unites with copper, forming the compositions known under the names of Bronze, and Bell-metal: by immersing thin plates of iron into melted tin, they become coated, and are then termed Block-tin, or Latten; which is manufactured into tea-canisters, and various culinary utensils.

Tin is likewise of use in medicine, both in the form of filings, and in a state of powder, especially as a vermifuge it has often successfully expelled the tapeworm, which had resisted the power of many other drugs ; but, the dose varying from a few grains to an ounce, it is one of those remedies which must be prescribed by the experienced practitioner.