A Treatise on Calico Printing, Of Colour-Making, A concise Display of several Tests or Reactives for ascertaining the qualities of various Articles in Use among Callico-Printers; with a few Experiments illustrative of the Modes of applying them.

A Treatise on Calico Printing, VOL. I-II
Printed for C. O'Brien, Bookseller, Islington, and fold by Bew, Paternoster-row: Richardson, Royal Exchange: Murray, Fleet-Street: And the Booksellers of Manchester, Glasgow, Dublin, &c.


(85) Sets of these tests may be had of several Chymists; or see Gottling'g Treatise, from which advantage is here taken.

(86) Thus, suppose it be required to know if iron be in alum, the solution of the alum must be in distilled water, otherwise the alum, though pure, may be dissolved in water that itself contains iron; of course, the iron that is detected will be no proof of the impurity of the alum. Or, a test itself may be impure; and have within itself the very substance it is wished to detect in another: hence, the effect must be obviously inconclusive; and hence, though these tests are here displayed, and just said to be certain, they can only be so, according as they are pure, or as they are properly applied; and to do which, requires no small share of chemical knowledge and experience; but in short, like other documents in this work, these are offered, to shew how needful a chemical knowledge is to a colour-maker, and as an inducement to try to attain it, rather than as any thing like what may be deemed perfect, or conclusive in point of practice, or fit for the chemical adept to look at; for the writer repeats, he does not address himself to proficients.

(87) Unless held in solution by fixed air.

A concise Display of several Tests or Reactives for ascertaining the qualities of various Articles in Use among Callico-Printers; with a few Experiments illustrative of the Modes of applying them. (85)

Note. It is to be understood though solution is not always mentioned, the articles mentioned are mostly used in a dissolved state, and the solvents, whether acids or water, must be perfectly pure. Water must be distilled. (86)

Lixivium of Prussian blue detects iron in any liquid by turning it blue. - Tincture of galls, by turning it violet or black. (87) — Tincture of litmus shews an acid by turning the liquid red — Paper coloured with brasil liquor an alkali by turning it violet, (acids turn it red again) — Turmeric paper detects alkaline salts by a brown (acids turn it yellow again.) - Litmus paper made red with vinegar shews alkaline salts, and earth held in solution by fixed air by the red turning blue — Vitriolic acid, shews fixed air, by a flight effervescence; alkaline salts and earths by a selenite or insoluble substance; ponderous earth, by a sparry one; nitrous acid, by the fumes produced by heating the liquor, moistning the stopper with vol. alk. and holding it over the heated liquor; marine acid by the same test — Nitrous acid detects fixed air by a flight effervescence; liver of sulphur by the smell of rotten eggs, and a white prec. — Lime water detects fixed air by a chalky prec. corrosive sublimate by a dirty yellow prec. copper by a green, emetic tartar by a white. - Acid of sugar detects lime by a selenetic prec. and rendering the liquid thick; magnesia by a. similar selenite — Vinegar detects vol. alk. by holding the outside of a glass tube over the liquor by fumes arising from the surface; nitrous acid by the same - Pure vegetable alk. detects magnesian earth by a white prec. likewise lime, earth of alum and iron partly — Mild veg. alk. precipitates all earths and metals held in solution by means of an acid; detects an acid by little bubbles of air; corrosive sublimate by a white or orange prec. — Caustic vol. alk. precipitates all the earths and iron almost in a metallic state: Copper by a blue. — Mild vol. alk. seperates all earths; detects copper by a blue — Soap shews fixed air or any other acid; or it is decomposed by earthy or metallic neutral salts, shewing a flaky substance (note 76) — Solution of silver in nitrous acid, detects vitriolic and marine acid, after saturating them witli nitrous acid first. It shews vitriolic acid by a white powder, the marine by a flaky substance;, liver of sulphur by a black prec. — Corrosive sublimate detects min. alk. combined with fixed air by an orange coloured prec. chalk by a white; hepatic air by a black — Sugar of lead detects vitriolic or marine acid by a white prec. liver of sulphur oi hepatic air by a dark one — Arsenic detects hepatic air by a yellow prec. — Epsom salt detects caustic alkaline salts by its being decomposed; - Sal ammoniac shews alkalies by augmentation of cold, and extrication of vol. alk. — Roman vitriol detects veg. alk. by a dark green; min. alk. by a bright apple green; magnesia by a dark sea green; lime by a yellowish green; earth of alum by a verdigrease green; sulphur or liver of sulphur by a blackish brown. — Cuprum ammoniacum detects arsenic by a yellowish green prec. — Highly reclified spirit of wine decomposes all solutions in vitriolic acid; and in large proportions the solutions in nitrous and marine acids, the metallic solutions excepted; it d«composes salts in solution by throwing them down. It likewise separates resinous and aetherio-oily substances. — Hepatic water, i. e. water impregnated with hepatic air, detects lead, or any deleterious metal by a dark prec. and iron by the addition of tincture of galls.

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