Dactylography

by Carpie Diem in Society, July 13, 2010

You must have watched many detective movies, read many such novels. We are all aware that finger prints form an important part of investigation in finding out the culprit. How exactly does a fingerprint actually help in catching the culprit? Is it that true that no two people in the world have the same fingerprints? If so, what about identical twins?

Synonyms: Dermatoglyphics, galton system, Fingerprint system

The system of Dactylography was first used in India by Sir william Hershel in 1858. sir Francis Galton systematised the system in 1892 and hence the name. Fingerprints are impressions of patterns formed by the papillary or epidermal ridges of the finger tips. At birth a fine pattern of ridges is seen on the skin of the bulbs of the fingers and thumbs, parts of the palms and soles of the feet.

Classification of Finger prints:

1. Loops (67%): a. radial, b. ulnar

2. Whorls (25%): a. concentric, b. spiral, c. double spiral, d. almond shaped

3. Arches (7%): a. plain, b. tented, c. exceptional,

4. composites (1%): a. central pocket loops, b. lateral pocket loops, c. twinned loops, d. accidentals

In a whorl the ridges form a series of circles or spirals around the core. While in a composite, there are a combination of two or more of the types, namely arches, loops or whorls.

The final identification of any fingerprint is not made by comparision of patterns. It is made by comparision of many details of characteristics which occur through out the ridge areas and by the sequence in which these characteristics occur. The characteristics may take the form of ridge endings, bifurcations, lake formations, or island formations.