In ancient Babylon (dating back to 1792-1750 B.C.), fingerprints pressed into clay tablets marked contracts.
The documents showing fingerprints date from third century B.C. China.
The earliest written study (1684) is Dr. Nehemiah’s paper describing the patterns he saw on human hands under a microscope, including the presence of ridges.
In 1788, Johann Mayer noted that the arrangement of skin ridges is never duplicated in two persons. He was probably the first scientist to recognize this fact.
Nine fingerprint patterns were described in 1823 by Jan Evangelist Purkyn.
Sir William Herschel (shown at the right), in 1856, began the collection of fingerprints and noted they were not altered by age.
Alphonse Bertillon created a way to identify criminals that was used in 1883 to identify a repeat offender.
In 1888, Sir Francis Galton (shown at the right), and Sir Edmund Richard Henry, developed the fingerprint classification system that is still in use in the United States.
In 1891, Iván (Juan) Vucetich improved fingerprint collection. He began to note measurements on identification cards, as well as adding all ten fingerprint impressions. He also invented a better way of collecting the impressions.
Beginning in 1896, Sir Henry (mentioned in the last entry on the previous slide), with the help of two colleagues, created a system that divided fingerprints into groups. Along with notations about individual characteristics, all ten fingerprints were imprinted on a card (called a ten card).
What Are Fingerprints?
All fingers, toes, feet, and palms are covered in small ridges.
These ridges are arranged in connected units called dermal, or friction, ridges.
These ridges help us get or keep our grip on objects.
Natural secretions plus dirt on these surfaces leave behind an impression (a print) on those objects with which we come in contact.
Latent fingerprints are those that are not visible to the naked eye. These prints consist of the natural secretions of human skin and require development for them to become visible.
Most secretions come from three glands:
Eccrine—largely water with both inorganic (ammonia, chlorides, metal ions, phosphates) and organic compounds (amino acids, lactic acids, urea, sugars). Most important for fingerprints.
Apocrine—secrete pheromones and other organic materials.
Sebaceous—secrete fatty or greasy substances.
Developing Latent Prints
Developing a print requires substances that interact with secretions that cause the print to stand out against its background. It may be necessary to attempt more than one technique, done in a particular order so as not to destroy the print.
Powders—adhere to both water and fatty deposits. Choose a color to contrast the background.
Iodine—fumes react with oils and fats to produce a temporary yellow brown reaction.
Ninhydrin—reacts with amino acids to produce a purple color.
Silver nitrate—reacts with chloride to form silver chloride, a material which turns gray when exposed to light.
Cyanoacrylate—“super glue” fumes react with water and other fingerprint constituents to form a hard, whitish deposit.
In modern labs and criminal investigations, lasers and alternative light sources are used to view latent fingerprints. These were first used by the FBI in 1978. Since lasers can damage the retina of the eye, special precautions must be taken.
Examples include retinal or iris patterns, voice recognition, hand geometry
Other functions for biometrics—can be used to control entry or access to computers or other structures; can identify a person for security purposes; can help prevent identity theft or control social services fraud.
The Future of Fingerprinting
New scanning technologies and digitally identifying patterns may eliminate analytical mistakes.
Trace elements of objects that have been touched are being studied to help with the identification of individuals.
To help with identification, other physical features such as eyes and facial patterns are also being studied.
. . . . . . . . . . . . . . . . . Summary
Fingerprints have long been used for identification, and in the mid-1800s were recognized as unique to each person.