The purpose of this paper is to present details of various coloring matters used to record information on paper. There are many technical problems connected with the formulation of inks for various purposes and the subsequent difficulties of the questioned document examiner hardly figure at all in the solution of the problems of the ink manufacturer. There are grave difficulties in fixing the date at which ink was used, because of the uncertainties of the subtle combination of conditions that operate in practice, on the rate of fading and ageing processes. New constituents become available at known dates and more is known about the properties of these new materials than about many of the older natural products. Thus technical advances can make the problems of determining whether various parts of a document are of the same origin or otherwise, somewhat easier of solution.