210

DYEING AND CALICO PRINTING.

carbonate of soda. The yield is 80 kilos, of amorphous chrysotoluidine.This is anew dissolved in 2000 litres of boiling water slightly acidulated, thesolution is filtered, and precipitated with 50 kilos, of caustic soda at 12° B.The precipitate is colledted, washed with cold water, and dried. It is treatedwith 8 kilos, of sulphuric acid, then with 200 litres of hot water, and kept ata boil for two hours. The solution, when cooled, is precipitated with greatcare by carbonate of soda, yielding 20 kilos, of a yellowish-maroon matter.The filtrate, containing chrysotoluidine nearly pure, is precipitated withcommon salt, and yields about 25 kilos. These two substances are thenpressed separately, and each is treated with the amount of sulphuric acidrequired to form a sulphate : 100 kilos, of the original crude matter, “ C,”yield 20 kilos, of the yellow-maroon matter, suitable for dyeing skins, and25 kilos, of chrysotoluidine. The formula originally assigned to chrysanilineby Hofmann, who discovered it among the residues of the manufacture ofroseine, was C 20 Hi 7 N 3 , corresponding to the percentage composition—

C.80-26

H.. 5-68

N. 14-04

Girard and Chapoteaut discovered chrysotoluidine when studying the actionof dehydrogenating bodies upon crystalline toluidine. Its formula is C 2 tH 2 jN 3 ;and its composition—

C.8o-oo

H. 6-66

N. I 3'33

The two bases are isomeric, if not identical. Chrysotoluidine forms well-defined salts with the acids.

Scheurer-Kestner obtained a yellow by dissolving mauveine in hydrochloricacid, and adding tin to the liquid. When all is dissolved common salt isadded, by which a yellow matter is thrown down resembling chromate of lead.This matter, collected, drained, and pressed, is exhausted with alcohol, inorder to separate the colour from the compound of tin. It dyes wool and silkof a yellowish orange.

Aniline Orange.

In the mother-liquors obtained in the purification of magenta made by thenitrate of mercury process there is found an orange colouring matter, which isseparated by precipitating the accompanying substances with common salt.The orange remains in the solution, and is obtained pure by evaporating andwashing the residue. It is readily soluble in alcohol, sparingly in hot water,and scarcely soluble in cold water. It dyes silk and wool a beautiful golden-yellow.

Zinaline, C 20 Hi 9 N 2 0 3 , was discovered by Vogel on treating a solution ofrosaniline with gaseous nitrous acid. It is insoluble in cold and sparinglysoluble in hot water. In alcohol, ether, and chloroform it dissolves readily.It is soluble in acids with a yellow, and in alkaline liquids with a blue colour.It dyes silk and wool a yellow-orange, which can be shaded into red by meansof ammonia.

ANILINE GREYS.

Castelhaz prepares an aniline grey by dissolving 10 kilos, of mauveine pastein 11 kilos, of concentrated sulphuric acid, at 66° B. When it is completely