At ACM’s Get a Clue camp, campers sharpen their logic and detective skills by investigating mysteries, solving riddles and cracking codes. One of the favorite activities at camp is to take each other’s fingerprint.
Imprinting the friction ridges of a person’s fingertip onto a surface is an easy way to uniquely identify someone. No two people have been found to have the same fingerprint and because of this, fingerprinting is used for many purposes, including crime solving.
The first modern, official use of fingerprinting as a way of identifying people was July 28, 1858 when a British magistrate, William James Herschel in India requested a local businessman put his hand print on the back of a contract. Herschel developed to the system because he thought locals felt more bound to a contract through this personal contact than if it was just signed. After 40 years of observing the fingerprints over time, Herschel also determined that fingerprints never change with age.
Although fingerprinting had been used as early as ancient Babylonia to seal clay tablets, this was the first time a government made fingerprinting a protocol to use to distinguish people. Almost 40 years later a policeman in Argentina began to keep fingerprints on file of criminals for investigating crimes. Now fingerprinting is a fundamental technology used in criminal investigations.
You can take your fingerprint at home. All you need is some tape, a pencil, some white paper and a magnifying glass.
1. Take the pencil and rub it on some scratch paper until you have a dark smudge of graphite.
2. Now press your finger firmly on the graphite until your entire fingertip is covered with graphite.
3. Take a piece of Scotch tape and place it on your fingertip and press gently.
4. Carefully remove the tape from your finger and stick it on a sheet of white paper. Be sure to label your print!
5. Use the magnifying glass to look closely at your prints and notice any patterns. Take someone else’s fingerprint and compare your prints!
Want to solve your own mystery by dusting fingerprints at home? Check out this out: http://www.omsi.edu/sites/all/FTP/files/chemistry/U7Dusted.pdf
