The Hebrew word deyohʹ, found only at Jeremiah 36:18, comes from a root word meaning “slowly flowing,” according to some scholars; others think it is from a root meaning “to be dark.” In the Christian Greek Scriptures meʹlan occurs only three times (2 Cor. 3:3; 2 John 12; 3 John 13), and is the neuter form of the masculine adjective meʹlas, meaning “black.”—Matt. 5:36; Rev. 6:5, 12.
Generally speaking, inks were made of a pigment or coloring material dispersed in a medium containing gum, glue or varnish that acted both as a carrying agent or vehicle and as a binder to hold the pigment on the surface to which it was applied. The oldest ink formulas, and the oldest specimens found, show that the pigment was a carbonaceous black, either in the form of amorphous soot obtained from burning oil or wood, or a crystalline charcoal from an animal or vegetable source. The pigments of red inks were iron oxides. Certain tinctures were also used by the ancients. Josephus says the copy of the Law sent to Ptolemy Philadelphus was written in gold letters. (Antiquities of the Jews, Book XII, chap. II, par. 11) If vegetable juices or dyes were ever used in inks they long ago disappeared due to their perishable nature.
To make the best inks much time was required to grind and disperse the pigments in their vehicles. The inks were then usually stored as dried cakes or bars, which were then moistened sufficiently by the scribe as he applied the ink to his brush or reed.
The Chinese inks long enjoyed the reputation of having the deepest tone and being the most durable. Documents written in some of these inks can be soaked in water for several weeks without washing out. On the other hand, inks were also made so they could be erased with a wet sponge or damp cloth. This may have been the basis for Jehovah’s saying, in a symbolic way, “Whoever has sinned against me, I shall wipe him out of my book.”—Ex. 32:33; see also Numbers 5:23; Psalm 109:13, 14; WRITING.