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DYEING AND CALICO PRINTING .

and to the proportion in which it has been spent in the first dyeing. Garanceuxfrom mixed Turkey (Levant) and French madder is equal, as it comes fromthe press, to from one-sixth to one-ninth of its weight of really goodgarancin. When dried it is equal to about one-third. It is of the utmostimportance to see that the garanceux is properly neutralised either in thedye-beck or before it goes in. An error on either side, that is to say, an in-sufficient or an excessive quantity of alkali, is equally injurious. The mostuseful matter for neutralising garanceux in the becks is bicarbonate of soda,which is very regular and mild in. its action. The proportion to be useddepends, of course, upon the degree of acidity; the highest amount requiredis about i lb. of soda to 70 lbs. of garanceux. If the acidity passes thislimit good results will not be obtained, and the garanceux should be washedover again. The lowest amount of soda required will be about 1 lb. to 100 or150 of garanceux taken in the wet state. The injurious effects of too muchsoda are perhaps even more marked than a slight deficiency. The coloursare dull and cloudy without brilliancy or solidity. A deficient quantity of sodais shown by a redness of the chocolate colours, poorness in the blacks, andgeneral bareness of the whole of the colours. The colours which garancin andgaranceux yield with properly mordanted cloth are the same as those frommadder; the whites are purer, on account of the absence of the soluble matterswhich stain them in madder dyeing. The colours will not stand a severesoaping, and cannot be brought to the same degree of brightness as thoseproduced from madder. These products are not much employed alone, butgenerally in combination with some of the cheaper dye woods.

Commercial alizarin or pincoffin has been sold by M. Pincoffs, ofManchester, since 1854. This material is remarkable for the beautifullilacs or violets it yields without soaping. It also admits of producingcombinations of lilacs with catechu, lilac and chocolate, and lilac andorange, which results cannot be obtained satisfactorily with madder orgarancin. This material, further, economises the mordants, and produceslilac shades, which may be graduated ad libitum as to cost.

Pincoffin is prepared by submitting garancin of good quality, and as neutralas possible, to the aCtion of dry or superheated steam. It may also be obtainedby heating garancin or fleur de garance to 200° C. on an oil or sand-bath. Itis very probable that the chief result of this operation is the destruction ofthe fawn-coloured resinous matter which is associated with alizarin. Hencethe colour cannot foul the purples or lilacs by its action upon the iron mordants.When fleur de garance, dried at ioo°, is aCted upon by fluoride of boron acarbonaceous matter is obtained, which, after washing with water, yields, onbeing heated with alcohol, a colouring matter^dyeing lilacs and purples as welland as beautiful as the commercial alizarin. The tinctorial value of the com-mercial alizarin is rather lower than that of garancin. Some authorities statethat about from one-sixth to one-fourth more of this material is required forthe saturation of an equal weight of mordant for lilac.

Mr. Higgin has devised another method of preparing commercial alizarin.He boils garancin with some carbonate of soda or a little ammonia. Theliquid, which is alkaline at starting, becomes acid after boiling for twenty-fourhours, when the garancin is converted into alizarin.

M. E. Schwartz has proposed to substitute for garancin a preparationobtained by mixing gradually in the cold fleur de garance with from four to