PRINTING ON CALICO. 



madder, to his beft work, and the other is bid by for infe- 

 rior purpofes ;] and a great deal of very excellent pnntmg 

 is now done in various parts of the knigdom, efpecially the 

 beft chintz-work and other furniture patterns. But, in 

 what is called faft-work, there is a great variety of qualities, 

 and fome of it little defervcs the name of permanent. 



The mention of permanent colours reminds us of a very 

 valuable green which was invented a few years ago by a 

 Mr Met of London, and which deferves to be noticed by 

 us This colour, which was fecured to him by his majefty's 

 letters patent, was produced by printing ground mdigo, 

 mixed with a peculiar kind of folution of tin, and m then 

 faftcnino- the indigo within the fibres of the calico by means 

 of that°procefs, which is well known to printers by the 

 technical" defigiiation of ch'ma-blue dipping. [China-blue is 

 produced thus : Indigo ground fine, and then thickened, is 

 printed uoon the cloth, and afterwards it is difiblved, and 

 chemically united to the fabric, by alternate immerfion in 

 a folution of fulphate of iron and in lime-water. A defcrip- 

 tion of this procefs has already been given very much in 

 detail, in our eleventh volume, part ii. under the article 

 DIPPIXG, in Calko-Prhitwg.^ After this the goods are to 

 be dyed in a copper of bark or weld, which converts the 

 blue to a green, and the whites are to be cleanfed by croft- 

 bleaching, &c. 



Upon this very ingenious procefs, Mr. Parkes has the 

 following obfervation. " Having," fays he, " formed a very 

 hio-h opinion of this invention, I procured feveral interviews 

 with Mr. Iflet, foon after he obtained the patent, and from 

 him was fully informed of the whole procefs. — This I 

 have fince repeated for the purpofe of verifying the detail in 

 all its branches ; and I am fatisfied that it is one of the 

 moll beautiful and permanent colours that has ever been 

 fixed upon cotton." 



There is, however, another mode of producing very beau- 

 tifid blues which has been much praftil'ed lately, and there- 

 fore deferves notice. This confifts in printing fome folu- 

 tion of iron, and then pafling the goods through a very 

 dilute and neutral folution of prufliate of potafh. The 

 pruffian blue which is thus formed upon the cloth may be 

 rendered tolerably permanent by a variety of expedients, 

 and this by means of any of the yellow dyes may afterwards 

 be formed to any (hade of green or of olive. 



In returning fromthefe digrefiions we muft not forget to 

 revert to that other kind of difeh?.rgc-\^'ork which we have 

 engaged to defcribe, and which we will now attempt as 

 concifely as is confiftent with perfpicuity and correclnefs. 



Here, the agent which is employed is the citric acid, and 

 this is ufed in various ftates of concentration according to 

 the purpofe to which it is to be applied, and the ftrength of 

 the ground intended to be difcharged. It is chiefly em- 

 ployed for the production of white figures upon felf- 

 coloured grounds produced by madder and fundry other 

 dyes. For this intention the acid, in whatever ftate of 

 concentration it may be, is mixed with either gum or with 

 pafte, [when citric acid is ufed for refift-vvork, it is always 

 mixed with gum fenegal and pipe-clay. The clay gives it 

 a greater body, and hkewife afts mechanically as arefifter,] 

 to a proper confiilcncy for the block, the plate, or the 

 cjlinder, and from thence it is transferred to the piece ; and 

 wherever it attaches, the mordant, whether iron or alumine, 

 is difcharged, and a delicate white arifes in its ftead. [ It 

 (hould be underftood, that the difcharge is printed upon the 

 mordants before the goods are dyed. In uling citric acid 

 for this purpofe, a portion of one ot the mineral acids is 

 fometimes mixed with it,] 



The acid here referred to is produced from the juice of 



limes or lemons, and formerly it was not employed by the 

 calico-printer until it was reduced to the utmoft point of 

 concentration, and appeared in a cryftalline form. Even 

 then, it was not thought fufficiently pure, l)ut was difTolved 

 again, and redilTolved and recryftallized, till it became as 

 white and pellucid as any other pure fait in a cryftallized 

 ftate, and was then generally fold for 36/. the pound, at 

 which high price it could only be employed on the beft 

 ftyles of work. Now, however, it is oftener ufed in the 

 brown, or firft ftate of cryftallizatifin ; and fome of the 

 larger printers purchafe lime juice, and concentrate it them- 

 felves ; and in many cafes, they ufe it largely both for dif- 

 charge and reiift work, without ever cryftallizing it at all. 

 More on this fubjeft may be feen in Mr. Parkes's Effay on 

 Citric Acid, in vol.iii. ot the Chemical Eflay, page i — 1 18. 



This mention of difcharge-work by citric acid, [Mr. 

 Thomfon, who has a print-work near Clitheroe, has taken 

 out a patent for difcharging the Turkey-red dye by means 

 of the citric and oxymuriatic acids ; and the work executed 

 in this way has a very pleafing effeft, j reminds us of another 

 fpecies of difcharge, which is employed by the printers of 

 Bandana handkerchiefs, and which we are under the pro- 

 mife of noticing before we conclude this memoir. 



The agent which thefe printers employ is the nitrous, 

 and fometimes the nitre-muriatic acid. It is ufed for the 

 purpofe of putting yellow figures upon blue filk hand- 

 kerchiefs. The following is the procefs which is prin- 

 cipally adopted. 



Aqua-fortis, or nitro-muriatic acid, of fuch a ftrength as 

 is fuitable for the kind of blue which is intended to he dif- 

 charged, is mixed either with gum tragacanth, or with flour 

 pafte, to a proper confiftence, and in this form it is printed 

 on the filk, by means of a common block, on which the 

 intended pattern is cut. The confequence of this is, that 

 wherever the acid attaches, there the original colour is, dif- 

 charged, and a yellow dye is produced in its place. The 

 pieces are then fteamed, by pafling them over a veflcl con- 

 taining boiling water, v/hich gives brilliancy to the colour 

 and finilhes the operation. 



If a ftronger dye than the ufual yellow, or even a deep 

 orange be defired, all that is neceffary is to immerfe the 

 goods, for a moment, in lime-water, or in a folution of lime 

 and potafli ; and by varying the proportions of thefe ingre- 

 dients a great variety of fliades may be produced. 



Recollefting, however, that this is a paper profefledly on 

 calico-printing, we muft not deviate too far from the path 

 we have prefcribed ; otherwife, there are many proceflls in 

 the printing of filks which are curious and interefting, on 

 which we might; copioufly expatiate. The Bandana hand- 

 kerchiefs which are printed upon cotton in imitation of 

 India goods, are produced by a very diff'erent procefs, and 

 which we have already defcribed under the article Dis- 

 charging of Colour, in vol. xi. part ii. 



Having been fpeaking of yellows, it may be worth men- 

 tioning, that there is a mode of producing yellows on 

 calico which is not very frequently praftifed, and yet has a 

 very good efleft. The procefs is as follows : 



A ftrong decoftion of bark, thickened with gum traga- 

 canth, is to be mixed with a portion of very pure muriate 

 of tin, and this, when printed with the ufual management, 

 will produce a colour of great brightnefs and durability. 

 We mention this the rather, becaufe very many pleafing 

 effefts may be obtained by this method which cannot be 

 produced in the ufual way, by means of the acetate ot 

 alumine, and any of the yellow dyes that may be employed 

 with it. 



There is one very important advantage whicli this mode 



poftefles. 



