Reissue of The Second Batch (#02-05012016) features a century old recipe for Arnold's Chemical Writing Fluid. This is an iron gall based ink, originally made in England. The ink goes on somewhat transparent with a blueish-green hue and then turns an extremely dark black within a minute or two.This ink produces some of the darkest black shades I have ever seen and super fine hairlines.
This recipe is an acidic ink iron gall ink, similar in acidity to Blots or Old World Ink. The original recipe states "This ink is destructive to nibs, for this, we know of no cure!".