146 COMPOSITION OF DURABLE INK. 



partitions as totally eradicate the traces of common ink, would 

 certainly be ati article of confiderable value in the material 

 compoiition of thofe writings, or legal inftruments, which are 

 intended to evince the traniadions of the day, and to ratify the 

 affairs of the future. 

 •The Invention The ancients were probably more interefted in thecompofi- 

 bjbfy'produced"^ 011 °^ permanently coloured ink than the moderns. When 

 fome rcmiflhefs every book was in manufcript, it would frequently be requi- 

 site tfink*' fiLe to tranf " cribe whole volumes, fometimes merely for the pur- 

 pofe of procuring a copy, at other times for the preservation 

 of the work itfelf j in either cafe, before the writer begun a 

 procefs fo tedious, it would be of confequence to felect fuch 

 materials as were the moll durable, in order to protract the 

 like neceffity, and alfo for the purpofe of enhancing the value 

 of his labour. But fince the invention of printing, the neceffity 

 of tranferibing has been entirely fuperfeded ; the manufcripts 

 of modern authors after publication, have been reduced to little 

 more value than objects of curiofity ; and writers have been 

 contented with fuch materials as are the cheapefl and eafieft to 

 procure. 

 Ink with vege- F° r a great number of years, the ink moft generally ufed by 

 table infufions European writers has been the infuiion of galls, and other 

 i"ron " P ™ ' atlringent vegetables containing gallic acid, rendered black by 

 fulphate of iron, and thickened by the addition of a little gum 

 or fugar. This compoiition is well adapted to the common 

 not durable. purpofes of writing and the difpatch of buiinefs, but its colour 

 is liable to fade: a composition of a more permanent colour is 

 therefore defirable, for writings which are required to retain 

 The colour may their primitive fignatures, and fuch as cannot be printed. In- 

 bereftored while d cec ^ f mce the difcovery of the method of totally difcharging 

 iron remain* on ^ ne traces of common ink "by the application of the oxigenated 

 the paper. muriatic acid, more ferious confequences are to be apprehend- 



Themoftferious ed f h u ; ver f al f f - the common atramentous fluid, 



objection to its * 



ufe is, that it than the decay of its colour from age; for it is well known, 

 ?fi b Vj tal,y that while the fulphate of iron remains on the paper, the co- 

 lour of the writing may bereftored, by warning the manufcript 

 withfrefh infufion of galls. 

 Means of pre- In the quarto feries of the Philofophical Journal (Vol. IV. 

 venting this by p 47$), there are feveral ufeful receipts for compofing ink 

 pigments. capable of refitting the oxigenated muriatic acid. The moft 



material difference, however, of the compofitions there re- 



2 commended 



