PARICESINE, the name given to a substance introduced for manufacturing purposes by Mr. Parkes of Birmingham. In that town; where so many kinds of small objects are made in countless thousands daily, it is of great importance to get hold of a cheap mate rial which will in some measure partake of the properties of ivory, bone, horn, tortoise shell, hard wood, iudia-rubber, or other natural substances. There are a umnbe'r of arti ficial compositions which to some extent do this, and Parkesine is one of these. It is said to be a mixture of pyroxyline (gun-cotton) and oil, hardened with chloride of sul phur. The pyroxyline is made from any vegetable fiber, as cotton and flax waste, or rags. According to another account, it is composed of castor oil, collodion, and wood spirit. For large and cheap objects other materials and solvents can be used, to which saw-dust, cork-dust, or pigments may be largely added.
In a paper read before the society of arts on the subject of Parkesine, and in a diecus sion which followed the reading, it was stated that this substance is not affected by sa water; it does not soften, like gutta-percha, by heat; it is a good insulator of electricity. even at a temperature of 212' F. ; it may be made either opaque or transparent, plain or colored; it will make a very strong joint after fracture; it will resist most of the com mon acids; its tensile strength is *Ilan that of india-rubber or gutta-percha. In
its hard form, the surface can lie so tr.( .ed as to imitate marble, tortoise-shell, amber, or malachite. It may be molded, pressed, turned, sawn, planed, carved, rolled, engraved, inlaid, or polished, according to the consistency given to it in the course of manufee (lire; or it may be made thin 'enough to use, when melted, as a varnish or protective coating or water-proolit,g. Among the many articles into which it may be fashioned, are included spinners' rolls and bosses, knife-handles, combs, brush-backs. shoe-soles. usubrella and parasol handles, buttons, book-binding, tubes, galvanic-battery cells, water proof fabrics, surgical implements, and telegraphic insulators.—It is probable that the eventual,success of compositions such as this will mainly depend on the price at which the material can he supplied per pound, compared with the prices of gutta-percha and india-rubber, the two substances which it is mainly intended to imitate or supersede; and the supply of these is necessarily exhaustible. Parkesine appears to have been first ma le on a large scale in 1802, but the manufacture of it has declined. There are, however, other materials in use which resemble it as respects composition.