The best and greatest quantity is found in England, in a mine near Keswick, in Cumberland. It is much used for pencils or crayons, for writing, drawing, &c.; for this purpose it is sawn into slips, and fitted into a groove in a strip of soft wood, as cedar, &c., over which another is placed and fastened with glue. What is Platina? A metallic substance, more recently discovered than the metals already described; and analogous to the perfect metals, especially gold,--many of whose properties it possesses. _Analogous_, bearing a resemblance. Whence is its name derived? It is the diminutive of _plata_, silver, to which it appears very similar; platina being a silver-colored metal, in small grains. _Diminutive_, a word lessening the meaning of the original. Whence is it obtained? Mostly from Russia, and, also from South America. Its color does not tarnish by exposure to the air, and appears to be equally permanent with that of pure gold; the metal is indestructible by fire. Platina is capable of being alloyed with all metals; is fused with difficulty, but by great labor may be rendered malleable: it is also the heaviest metal, being 21 times heavier than water. _Permanent_, lasting. Are there any other Metals besides those already mentioned? In addition to the metals known and used by the ancients, the chemical science of later ages has, by decomposing other earths, added more than thirty to the number of metals, some of them more curious than useful; several of these are lighter than water. All the metals possess different and distinct properties from each other. They are divided into two classes, the malleable and the brittle metals. These last may be again divided into two others,--namely, those which are easily, and those which are with difficulty fused. What do you mean by Metallurgy? The art of obtaining metals from their ores, comprising the processes of assaying, refining, smelting, &c. By assaying is meant, the particular manner of examining an ore or mixed metal, according to its nature, so as to discover not only what metals and what proportions of metal may be obtained from it, but also what other mineral substances or earths may be contained in it. What do the terms Refining and Smelting signify? Refining is the art of rendering the metal free from all impurities. Smelting means the melting of a metal from its ore in a smelting furnace, in order to separate the metallic parts from the sulphur, arsenic, and the earthy and stony substances with which they may be combined. What is Sulphur?