ANILINE YELLOWS AND ORANGES.

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The aniline browns are generally dissolved in boiling water, and useddiredtly for dyeing. In case of wool and silk no mordant is required. Uponcotton they are fixed by processes similar to those already indicated for otheraniline colours. The shades produced can be modified at discretion by theaddition of acids to the dye-bath, or of magenta in larger or smaller amount.

In printing, a garnet-brown may be produced upon the fibre by the following

process, due to Kcechlin :—

Solution of magenta, 50 grms. to a litre of alcohol .. 25 centilitres.

Gum-water.75 »

Oxalic acid.5° grms.

Chlorate of potassa.25 ,,

By adding successively increasing doses of neutral extract of indigo, theshade may be modified up to a black. If a redder garnet is required the pro-portions of oxalic acid and of chlorate of potassa should be diminished. Fora yellower shade any yellow lake may be added to the colour, provided it doesnot contain oxide of tin for its base.

ANILINE YELLOWS AND ORANGES.

Chrysaniline, or phosphine, was discovered by Nicholson, and is manufac-tured by the firm of Brooke, Simpson, and Spiller. Their process is keptsecret, but the following method is given by Girard and De Laire :—topo kilos,of the crude residue from the manufadture of roseine are dissolved in 12,500litres of boiling water, to which 85 kilos, of hydrochloric acid have beenadded. Violaniline remains insoluble. The boiling solution is filtered, and tothe filtrate 125 kilos, of hydrochloric acid are added. On cooling, a precipitate(A) is formed, consisting of about 40 to 45 kilos, of hydrochlorate of rosaniline,mixed with a little rosaniline and resinous matters.

The filtrate is treated with 625 kilos, of common salt. The precipitate, 30to 35 kilos., is a mixture of mauvaniline and salts of rosaniline. Name it A.The mother-liquor, filtered off, is saturated with 83 kilos, of soda-ash, con-taining 58-64 per cent of adtual soda. The product, B, 205 to 210 kilos.,consists almost entirely of salts of rosaniline, and a very small quantity ofsalts of chrysotoluidine.

To the filtrate 37 kilos. 500 grms. of soda-ash are added, when a precipitateis formed, 37 to 40 kilos., consisting of chrysotoluidine, with a small trace ofrosaniline: 100 kilos, of this last precipitate are dissolved in 2500 litres oflime-water, containing a little lime in suspension. After boiling, the whole isfiltered, and the filtrate collected in a crystallising-vat containing hydrochloricacid. On cooling a salt of rosaniline is obtained, containing a trace of chryso-toluidine, and known as yellow magenta. The insoluble residue contains theyellow colour. To remove the lime it is heated in a vessel of enamelled cast-iron, along with a very little water and hydrochloric acid, just sufficient tosaturate the lime. The chrysotoluidine melts, floats on the surface, and isremoved with a skimmer and washed a time or two in a little cold water. Toremove the last traces of rosaniline 100 kilos, of the skimmings are dissolvedin 2000 litres of boiling water, with 100 kilos, of hydrochloric acid. Whenthe solution is made 10 kilos, of zinc are added, and the whole is kept at theboil for eight hours. It is cooled, filtered, and precipitated with 20 kilos, ofcommon salt, the acid being almost entirely neutralised by the addition of