448 TIN. Geognostic and Geographic Situations, Europe.—It occurs loose, and in small quantities, a!on£ with stream tin, in alluvial deposites (stream-works), at Sithney, St Creet, Gossmoor, Pentowan, Gavrigan, St Mewan, St Columb, St Roach, and St Denis, in Corn wall. America.—It is one of the most common ores of tin in Mexico. In that country, it is found at Guanuaxuato, (Goanachuato), in veins that traverse trap-porphyry, and is also met with in alluvial deposites *. Observations. It very much resembles Brown Hematite, but can be distinguished from it by its colour-suite, greater hard ness, and higher specific gravity. ORDER XII- * Some time ago, Mr Mawe of London sent me a drawing of a mass of Mexican wood-tin, now in his possession, which weighs ten ounces and* haif. It is the largest specimen of this ore I am acquainted witlh