Laboratory Notes in Household Chemistry; for the Use of Students in Domestic Science

by Hermann Theodore Vulté

Ce livre historique peut contenir de nombreuses coquilles et du texte manquant. Les acheteurs peuvent generalement telecharger une copie gratuite scannee du livre original (sans les coquilles) aupres de l'editeur. Non reference. Non illustre. 1910 edition. Extrait: ...in the excess of oil present, but not in water. During the drying operation, the oil absorbs oxygen and solidifies to a tough elastic body. This latter action is however quite slow, hence driers (compounds of manganese) are used to hasten the absorption of atmospheric oxygen. Spirits of turpentine (C10H18) commonly called "Turps" are useful in thinning the paint mass and causing it to penetrate the freshly painted surface. Turps also dulls or flats the otherwise glistening surface of the dried paint, but renders it at the same time noticeably susceptible to the action of moisture. As in the case of water paints, mineral colors ground in oil are used for tinting. The following is a list of the most lasting: Reds--Indian, Venetian, Tuscan (oxides of iron). Yellows--Ochre (oxideof iron), Chrome (chromate of lead). Brown--Umber (manganese clay) Sienna. Blue--Prussian Blue. Green--Prussian Blue and Chrome Yellow. Black--Lamp-or Bone-black (carbon). Oil paints are best applied in at least three successive coats. First or priming coat is pure white lead and oil with abundance of turps. This coat sinks in and dries rapidly. Second or body coat is pure zinc and lead base, linseed oil and drier. It is much thicker than the previous coat and takes longer to harden and dry. Finish coat is much like the body coat but thinner; in rare cases it may contain a little turps for flattening effect. Varnishes are of two kinds--spirit and oil. Spirit varnishes consist of gum resins dissolved in alcohols; for instance, shellac and the less common lacquers. As the solvent evaporates, the gum remains as a continuous coat. Because of their light color and transparency, they are much used in covering wood-work....

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