172 Scientific Intelligence. 
by muriate of manganese can be made slowly, and is consequently 
more certain.— Bib. Univ. Juin, 1828. 
9. New indelible ink, by Henry Braconnot.—This enterprising 
chemist describes an ink, which, agreeably to his account of its pro- 
perties, will prove to be a valuable accession to the arts of writing, 
marking, and dyeing. 
Being engaged, conjointly with M. Parisot de Nancy, in the pro- 
duction of a cheap and solid brown dye, he torrified with potash, vari- 
ous organic matters, and thus ascertained that substances containing 
the most azote, such as flesh, leather, horns, &c. gave the deepest 
color. From a hint, also, which they derived from Fourcroy, he 
was induced to add to the mixture, prior to torrefaction, flowers of sul- 
phur, and by this means they produced a deep chesnut brown, more 
substantial than any like color known to the dyer. 
‘Phe proportions which he found most convenient, and the method 
of proceeding were to dissolve 20 parts of Dantzick potash in boiling 
water, and add to the solution 10 parts of animal matter, minutely 
divided, (leather parings from the tanners were found to be conven- 
ient,) and 5 parts of flowers of sulphur. These are boiled to dryness 
in a cast iron pot, and the heat is urged until the mixture softens, tak- 
ing care to prevent ignition, and, after adding by degrees a suitable 
portion of water, the fluid portion is filtered through a loose cloth. 
There is thus produced a deep colored dye or ink which can be easi- 
ly preserved in a well stopped bottle. A single pen full of this ink 
is said to be sufficient to write one or two quarto pages, and that it 
possesses all the desired properties of an indestructible ink, flowing 
more freely from the pen than common ink, and resisting the most 
powerful chemical agents. 
A strip of paper written with this liquid, treated with a concen- 
trated solution of boiling caustic potash, was mostly destroyed, but 
the scraps which escaped destruction, plainly showed the letters in 
their perfect shapes. Paper, written with the same liquor, immersed 
for an instant in moderately concentrated sulphuric acid, was dissolv- 
ed, passing in part to the condition of gum, but on the thin undis- 
€d portion, the writing might easily be read. 
The characters of this liquor, experienced no change in twenty 
= in concentrated nitric acid, even assisted by heat, to ar 
et hot quite sufficient to destroy the paper entirely. 
