v = 
F On the Preparation of Writing Ink. AS9 
the liquor whil/? hot, fuffer it to cool, and make up the 
quantity equal to five quarts by the further addition of cold 
water. To this cold decoétion put one pound averdupois 
weight of blue galls, or 20 ozs. of the beft galls in forts, 
which fhould Be firft rasan bruifed; 4 ozs. of fulphat of 
iron, calcined to whitenefs;. 4 oz. of the acetite of copper, 
which fhould be triturated in a mortar, moiftened by a little 
of the deco&tion gradually added till it be brought to the - 
form of a fmooth palte, and then thoroughly intermixed with 
the whole mafs. Three ounces of coarfe brown fugar, and fix 
ounces of good gum Senegal, or Arabic, are alfo to be added. 
Thefe feveral ingredients may be introduced one after the 
other immediately, contrary to the advice of fome, who re- 
- commend the gum, &c. to be added when the ink is nearly 
- made; as gum, ew ever, 1s at prefent exorbitantly dear, three 
or four ounces will be found fufficient, with only one and an 
half ounce of fugar, unilefs, for particular purpofes, it is wanted 
_ to beara higher glofs than common. In regard to the ufe 
of fugar, which f have here recommended, I hope I fhall not 
 ‘trefpafs in remarking, that my obfervations, on a very exten- 
- five feale, are coincident with thofe of M. Ribancourt, who 
 fays, that a degree of fluidity is by its means imparted, which 
_ allows the dofe of gum to be enlarged confiderably beyond 
_ what it would bear without it; and it is thereby rendered 
_ lefs liable to clog the pen, which, efpecially when the nib is 
' very fine, if it does not flow freely, quits it fo flow as unplea~ 
fantly to retard the writer, and is totally unfit for fine manu- 
_ feripts; befides, by fuch an union of gum and fugar, a de- 
_ gree of confiftency is given to the liquor, which enables it to 
 fafpend a much greater portion of colouring matter than 
otherwife could be effected; a circumiftance of the greateft 
importance to its hue and permanency. © It is far from my 
_ defign, in thus tranfmitting my ideas, to induce a fuppofition 
that it is eaaét/y after this manner that I, or any other perfon 
_ who fupply ink by wholefale, compound it; fo far from it, 
- that the firft coft of one gallon, on the plan here fuggefted, 
_ would exceed twice the fum which: is ufually paid for it to 
the manufacturer, although by retail it is difpofed of at an 
_ €normous rate, For private perfons, cc who with to 
be 
