Examination of Line Crossings by Scanning Electron Microscopy

A document examiner is often faced with determining the age of certain writing, whether done by ball-point pen, pencil, ink, typewriter, or something else; the problem is almost unsolvable because no method exists that yields reliable and direct results. Ways and means have often to be found that permit an indirect determination. One of the most important factors in this connection is the investigation of line crossings. If the writing sequence of two crossing lines can be determined, it is then possible to estimate accurately the age of one writing characteristic in relation to the other. For instance, the frequently posed question as to whether a signature on a contract was made before or after the text was written can be answered.