U3S PREPARATION OF INDELIBLE fN#. 



low heat, and when difiblved runs freely from the pen: I have 



known fome artifts draw with this in preference to ink, becaufe 



its colour harmonizes better with other materials alfo ufed in 



drawing, and becaufe it is indelible, as it itrikes immediately 



into the paper, and if it is not thick, will ftrike through it: by 



this means every ftroke made with it is vifible through every 



colour that is waflied over it. 



.Afphaltum in It feems then that if a folution of afphaltum was made in 



ipint of turpen- ^pj r j t f turpentine, and fo much of the folution of amber was 



confiftent with added as would give it due confidence, and the fineft lamp 



Solution of am- black to give it colour, a perfect ink would be formed, and 



loured with lamp poffeifing thofe properties Mr. Clofe feems to defire; for, fup- 



biack, would pofmg the other materials could be removed, fo much of the 



colour as depends on the afphaltum would be indelible, except 



by fuch means as would deftroy the paper or parchment. 



The drying oil Even the fmall quantity of drying oil introduced into the 



m 'Sdincreafc varmfll ' would be ufeful in this refpeft; for it is well known, 



the difficulty of that if oil is dropped upon white paper, though the mark is 



chiitcration. fcarcely vifible at firft, in a year or two it will become a dark 



yellowifh brown : it feems as though the oil changes the paper 



fo much that its colour can never be recovered, at leaft thofe 



who undertake to reftore the white colour of old prints, always 



make an exception to fpots of oil. 



If this hint fhould be thought deferring any notice, you will 

 have the goodnefs to make what ufe you pleafe of it. 

 I am, Sir, 



Your's, &c. 



T. SHELDRAKE. 

 JVb. 50, Strand, July 6, 1802. 



Copal would ^' ^' * believe Mr. Clofe will find himfelf miilaken as to 



probably be dif- the iniblubility of copal when ufed in his ink. So powerful is 



charged from ^ j n fl uence f camphor upon it, that if copal be reduced to 

 paper by cam- x . ... 



fhorated fpirit. powder, and a little camphor is rubbed into it, it immediately 

 begins to foften, and the whole foon becomes a coherent mafs; 

 and though copal is not foluble in alcohol alone, if camphor is 

 added, it diflblves as eafily in the compound as the fofteft refin 

 would. It is therefore extremely probable, that, if a paper 

 written with his ink was waflied with camphorated fpirits, the 

 writing would be removed with very little difficulty. 



V. Ohfervations 



! 



