Aniline Ink Paper.
To make aniline ink paper thick filtering paper is soaked in a very concentrated solution of an aniline dye and allowed to dry; it may then be soaked again to make it absorb more color. With a little attention it will not be difficult to prepare the paper so as to have a known quantity of coloring matter in a square of a given size. Paper prepared as above is very convenient to have when traveling; when one wishes to write, it is only necessary to tear off a small piece of the paper and let it soak in a little water. Aniline blue paper may also be employed conveniently for bluing in washing.