Who Stole Herman Tweed?
Who Stole Herman Tweed?


Try your hand at forensic science--where law and science intersect.


To collect and identify fingerprints and to learn about forensic science


  • Pencil
  • Two plain white index cards
  • Transparent tape
  • Magnifying glass


Rub the lead of the pencil back and forth across one of the index cards until most of it is covered. Next, press your index finger firmly on the card until your fingertip is covered with lead that rubs off the card. Using the tape, cover the smudged fingertip. Then press firmly so that the print will transfer to the tape. Remove the tape from the index finger and press the sticky side of the tape onto the clean index card. Use the magnifying glass for a closer look.


A copy of the print is left on the sticky side of the tape. The pattern formed by the ridges of the fingertips is called fingerprints. There are three basic patterns...the whorl, loop, and arch. Everyone has a different fingerprint. Even identical twins do not have the same fingerprints. A forensic scientist analyzes physical evidence taken from a crime scene to help solve a case. This may include taking detailed notes and pictures, looking for fingerprints and sole prints, searching for fibers from clothing, and analyzing body fluids.