Fingerprints- An Introduction

INTRODUCTION

Everything we touch leaves behind our unique impression on it, which is Our fingerprints.

No two people have exactly the same fingerprints. Even identical twins, with identical DNA, have different fingerprints.

Fingerprint identification is also known as “Dactyloscopy”.

Fingerprints are the tiny ridges, whorls, and valley patterns on the tip of each finger. They develop from pressure on a baby’s tiny, developing fingers in the womb.

CLASSIFICATION OF FINGERPRINTS

By FRANCIS GALTON

A well-known British scientist sir Francis Galton published his first book on fingerprints in 1892. His important work includes a method for the classification of a fingerprint which is divided into three groups-
a. Arch
b. Loop
c. Whorl

By WILLIAM J. HERSHEL

While working for the East India Company in Bengal, India, Sir William James Herschel first used fingerprints on native contracts. After a decade, he had accumulated a file of fingerprints.

By EDWARD HENRY

Henry’s Classification of Fingerprinting was accepted as a common practice throughout England, its territorial holdings, and the United States.

Under the henry system, fingerprints are divided into two classes:
•Those which are given a numerical value. (whorls and composites).
•Those which doesn’t give numerical value. (loops and arches).

All patterns are divided as follows:

The henry classification system assigns each finger A number according to the order in which it is located in the hand, beginning with the right thumb as the number 1 and ending with the left pinky as the number 10.
• The system also assigns a numerical value to fingers that contain a whorl pattern; fingers 1 and 2 each have a value of 16,
• Fingers 3 and 4 = 8,
• Fingers 5 and 6 = 4,
• Fingers 7 and 8 = 2,
• Final two fingers = 1.
• Fingers with a non-whorl pattern, such as an arch or loop pattern, have a value of zero.
• The sum of the even finger value is then calculated and placed in the numerator of a fraction.
• The sum of the odd finger values is placed in the denominator.
• The value of 1 is added to each sum of the whorls with the maximum obtainable on either side of the fraction begin 32.
• Thus, the primary classification is a fraction between 1/1 to 32/32, where 1/1 would indicate no whorl patterns and 32/32 would mean that all fingers had whorl patterns.

By JUAN VUCETICH

Vucetich is credited with the first positive criminal identification as, in 1892, he was able to extract a set of prints of a door and thus identify a woman as the culprit in a double homicide.

✴ CHARACTERISTICS OF FINGERPRINT

🖐 Class Characteristics

Class characteristics are the characteristics that narrow the print down to a group but not an individual.

The Three Fingerprint Pattern Types Are:

1. Arches

✔Arches are the simplest type of fingerprints formed by ridges that enter on one side of the print and exit on the other. No deltas are present.
✔About 5 % of the world’s population have arch patterns.

Arch pattern

2. Loops

✔ Loops must have one delta and one or more ridges that enter and leave on the same side. These patterns are named for their positions related to the radius and ulna bones.
✔ About 60-65 % of the world’s population have loop patterns.

Loop pattern

3. Whorls

✔Whorls have at least one ridge that makes (or tends to make) a complete circuit. They also have at least two deltas.
✔About 30-35 % of the world’s population have whorls patterns.

Whorl Pattern

Individual characteristics

👉 Individual characteristics are those characteristics that are unique to an individual.
👉 They are tiny irregularities that appear within the friction ridges and are referred to as Galton’s details.

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