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EUCAFNE

A white, crystalline, organic compound used as a substitute for cocaine.

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EUSOL

A proprietary antiseptic, solution containing hypochlorous acid; prepared by interaction between socalled chloride of lime and boric acid.

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ESTER GUMS

Substitutes for the harder natural resins made by combining the acid resins with alcohols, such as glycerine. They are soluble in oil and turpentine, have acid values as low as from 2 to 20, and are stated to be much more suitable than ordinary resin for use in making varnishes and enamels. To prepare them, the softer parts of the resin are removed by distillation in a vacuum or a current of superheated steam, and the residue is heated with an equivalent proportion of glycerine, phenol, or naphtnol, to a high temperature with a dehydrating agent. Resin esters can be formed with glycerine by heating together at from 280 degrees to 300 degrees C., and passing a current of hydrochloric acid gas, cai bon dioxide, or air through the mixture. Ester gums are used in making enamel paints, and more particularly for waterproof varnishes for boats, yachts, etc.

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EMERALD GREEN

A pigment, bring a combination of metarsenite and acetate cf copper 2,C2H3022.

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EMERY

A native form of alumina coloured with oxides of iron and manganese used as an abrasivethat is, for grinding and polishingby reason of its hardness.

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ESTERS

Many alcohols react with acids, like metallic hydroxides and form what are termed alkyl salts or esters; for example, ethyl alcohol and acetic acid by interaction give ethyl acetate and water CjHjOH + CH3CO,OH = CH3,COO,C2H6 + H,, the replaceable hydrogen atoms of the carboxylic group being exchanged for alkyl radicals, and the process is known as esteritication. The esters so produced from the fatty acids are more or less volatile neutral liquids which are readily hydrolyzed when heated with water or alkalies or acids back again into the corresponding alcohols and acids. Monobasic acids such as nitric acid yield only one kind of ester termed “normal or neutral esters.” but dibasic acids yield two series termed “acid esters” and “neutral esters” thus ethyl nitrate is N03, while we have the two etbyl sulphates,HS<, and and the several fatty acids thus stearinC3Hjj3 + 3KH0 = 3K + C3H63 Some of the better known commercial esters are alphabetically listed below: The amyl esters of formic, acetic, and hexoic acids are among the odorous constituents of apples.

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EBONY

The black heartwood of Diospyros ehentim, which grows in Ceylon, Madagascar, etc.

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EXTRACTS

A pharmaceutical term descriptive of the concentrated preparations obtained by evaporation of infusions or extracts prepared by the action of solvents.

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ENAMELS

are fusible glasses rendered opaque by dissemination throughout the mass of a vitreous substance infusible at the temperature at which they are made, such as oxide of tin. Up to about 900 degrees C. the tin dioxide exists in a state of suspension in the enamel, but if that temperature be exceeded, real solution takes place and the opacity is diminished. Titanic oxide, zirconia, and other vitreous substances can be employed in place of the stannic oxide. The opacity is due to the difference in refractive index, and is obtained in some cases by the use of arsenious oxide, calcium phosphate, cryolite, etc. Platinum and iridium oxide are sometimes used to produce greys in enamels, and a great variety of other substances can be used according to the desired tint and other characteristics. One kind of enamel used for glazing castiron articles, such as saucepans, consists of powdered flints ground together with calcined borax, fireclay, and a little felspar, made into a paste and applied to the surfaces, which are then dusted over with a glazemixture composed of felspar, sodaash, borax, and a little oxide of tin, after which they are dried and fired at a red heat.

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ENAMEL PA

Paints ready mixed with varnish so that they dry with an enamelled face or gloss.

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