INKS. 3Q1 



pulverized gum-arabic, and preserving it in a glass bottle, or glazed 

 earthen vessel, slightly covered with paper. 



Van Mons has applied the discov< ries of Proust to the prepara- 

 tion of common writing ink. He has found that the sulphate of iron 

 calcined to whiteness, always gives a most beautiful black pn-ri. 

 pitate. By the following mixture, he obtained excellent ink : 

 galls 4 oz. ; sulphate of iron, calcined to whiteness, 2| oz. ; and two 

 pints of water. The whole must be left to macerate cold for 24 

 hours: then add gum-arabic \(i drams, and preserve it in a stone 

 jar open, or covered merely with paper. Chaptal has also em. 

 ployed the calcined sulphate, in connection with the decoction of 

 gall nuts and logwood. 



M. Desormeaux, Junr of Vine court, Spitalfields, who has long 

 been in the habit of preparing ink upon a large scale, has commu- 

 nicated to the Philo.inphical Magazine, a valuable paper on the 

 subject, from which the following directions are extracted. In six 

 quarts, beer-measure, of water, (it does not appear of importance 

 whether it be rain, river, or spring water) boil four ounces of the 

 best Campeachy logwood, chipped very thin across the grain (the 

 boiling may be continued near an hour) ; adding from time to time 

 a little bulling water, to compensate for weight by evaporation. 

 Strain the liquor, while hot ; sutler it to cool, and make up the 

 quantity equal to five quarts, by the further addition of cold water. 

 To this cold decoction, put one pound averdupois waste of blue 

 galls, or 20 oz. of the best galls in sorts, which shonld be first 

 coarsely bruised ; 4 oz. of sulphate of iron, calcined to whiteness ; 

 \ oz. of the acetite of copper, which should be triturated in a mor- 

 tar, moistened by a little of the decoction gradually added till it be 

 brought to the form of a smooth paste, and then thoroughly inter, 

 mixed with the whole mass. Three ounces of coarse brown sugar 

 and six ounces of good gum Senegal, or Arabic, are also to be 

 added. These several ingredients may be introduced one after the 

 other immediately, contrary to the advice of some, who recom- 

 mend the um, &c. to be added when the ink is nearly made; 

 as gum, however, is at present exorbitantly dear, three or four 

 ounces will be found sufficient, with only one and a half ounce of 

 sugar, unless, for particular purposes, it is wanted to bear a higher 

 gloss than common. As the common writing inks arc dclible by 

 many of the acids, especially the oxy muriatic, several chemists and 

 others, particularly M. Pitel of Minden, Dr. Leutin, 



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