Named for the Frenchman (Louis Braille) who invented it in 1821, Webster defines Braille as 1) a system of printing and writing for the blind, in which letters, numbers and punctuation are made with raised dots distinguishable by the fingers or 2) the characters used in this system.



To the Document Examiner however, Braille refers to something entirely different.  As a writing instrument travels across a soft writing surface, it creates an indentation, or trough...  Indented Writing, or Braille.



A Document Examiner will look for Braille, for example, on an anonymous letter.  When examined closely, it is not uncommon to find a "first draft" of the letter in Braille.  The author first composed the letter in their natural hand, removed the page and re-wrote it in a disguised hand on a subsequent page.  The indented writing from the "first draft" then appears on the anonymous letter.



Two methods might be employed to detect the Braille:



1. Braille can be successfully detected using simple oblique (side) lighting.  The images at the right are two photographs of the same document taken with different lighting techniques.  The top photograph was taken with direct lighting and the bottom with oblique lighting.  The indented writing becomes quite clear.

2. The ESDA (electrostatic detection apparatus) machine was designed specifically for this purpose and is infinitely more sensitive.

Below are 2 images of the same anonymous letter.  The image on the left is a photograph of  the letter as it appears to the naked eye.  The image on the right is the ESDA image.  The writing that appears white on the ESDA image is the visible ink text.  The black writing is the once-invisible Braille.