The Chinese did manufacture paper from the bark of the small branches of a tree of the mulberry genus, (_Morus Multicaulis_?) and also from old rags, silk, hemp, and cotton, as early as the second century of the Christian era; and it is supposed that from them the Arabs derived their knowledge of paper-making, an art which they introduced into Europe in the former half of the twelfth century, when the first paper-mill was put in operation in Spain, then under the Moorish dominion; and, in 1150, this article, as manufactured by them, had become famous throughout Christendom. [We use the words Arab and Moor indiscriminately here. The former is the name of the race; the latter is limited to that portion found in Northern Africa. The Moor is the Arab of the WEST, (Al Mogreb, El Gharb,) in the Arabic, denominated MOGREBYN,—a word which in Roman and European mouths has smoothed and softened itself into a form suggestive of the origin of _Maurus_ and _Mauritania_.] Now, without coming to a positive conclusion on this subject, we feel authorized to pronounce what appears to be a reasonable opinion, derived from all the facts which we have just placed before the reader,—that the introduction of writing-paper among Europeans, was the occasion and cause of the invention and general employment of modern writing-ink by them. The fact that the vegetable astringents form a deep or bluish black color, when combined with a salt of iron, had been known from time immemorial. Among the Romans, the _atramentum sutorium_,—“shoemaker’s ink,”—was applied to a solution of sulphate of iron employed by them, as it is even to this day, by workers in leather, to blacken the surface of that material. This it does by uniting chemically with the tannin and gallic acid, by which the hide was converted into leather, whose blackened particles are therefore essentially identical with modern ink. The “copperas-water” is to be found in every shoemaker’s shop, where it is used to color the cut edges of the heels and the rest of the soles. As soon as the difficulty of writing with convenience and rapidity on paper, with the ancient carbonaceous ink, became manifest, the resort to the _atramentum sutorium_ as a substitute for the _atramentum scriptorium_, was a matter of course, and was but a simple adaptation of a familiar substance to a new purpose, requiring no great ingenuity, and no invention whatever.