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Published:March 16th, 2009 09:50 EST
Fingerprints: A Look at What They really Mean

Fingerprints: A Look at What They really Mean

By Saly Alhady

"Fingerprints" is a common word associated in our minds with crimes, victims, witnesses, or suspects, but it doesn`t take any time from us to think about it or about the science it is based on.

Simply, it is an imprint made by the pattern of ridges on the pad of a human finger. These ridges are known as dermal ridges, and there are three basic fingerprint patterns: Arch, Loop and Whorl .The process of analyzing fingerprints is known as dactylography.

Occasionally, the two basic ideas scientists believe after more than 140 years of studying fingerprints are:

-An individual`s fingerprints never change; in 1858 a British magistrate named William Herschel realized that each print was unique and unchanging.

-The ridges on the fingertips of all persons have three characteristics (ridge endings, bifurcations and dots), but no two fingerprints are identical-- not even for twins. (it was the research for the comprehensive book Finger Prints, published in 1892 by Sir Francis Galton, that became known as the Galton-Henry system, which eventually became the FBI-NCIC system)

We can`t be sure about the exactly date of the origin of fingerprint science, but we have some significant dates, and can say it was sometime in 1880, initiated when Dr. Henry Faulds published his first paper on the subject in the scientific journal Nature.

There had been a tradition in some countries to use one fingerprint as a signature, while footprints are used to identify infants at hospitals. Also, a person`s fingerprint can be used as a biometric method to identify human individuals.

Actually, fingerprints give great assistance in solving many complicated cases, as links and matches between a suspect and a crime. There are  techniques to deal with fingerprints, the most popular developing technique is Dusting; simple because most people`s fingers carry a coating of perspiration and oil. When fingers come into contact with any relatively smooth surface, the contact leaves the oil from between the ridges, in the shape of the print, so that using colored powder will make it visible.

At least three other methods besides dusting exist, like the Iodine fumes which work well on porous surfaces such as paper and unfinished wood.

 Another method is Ninhydrin spray, a particularly useful method for all kinds of surfaces, because Ninhydrin will develop prints made over 30 years ago and produces a blue-violet color on the developed print.

Another method is Silver Nitrate t, which involves spraying silver nitrate onto a surface with an aspirator, then exposing the area to ultraviolet light. This method produces a clear, crisp print because the chemical picks up on the salts in the perspiration.

Not all people believe that fingerprint identification is a science, but maybe this will help make them reconsider.