Fingerprints Essay Example For Students

Fingerprints Essay Fingerprints are one of the most important things that link a suspect with acrime scene. Even though that fingerprints are not always left by a criminal,the crime scene should still be examined for them. All people have distinctfriction ridges on the skin of the fingers. In leaving an impression, an outlineof the ridges is transferred and duplicated by oil, sweat and other substanceson the object handled. The impression is usually not visible. Fingerprints notvisible are called latent prints; so something must be done to make themvisible. The most common way to make them visible is to dust anobject with fingerprint powder. The color of the powder should contrast with thesurface, such as black powder on light-colored backgrounds and white powder ondark. An alternative to using powders, is using chemicals. The most common touse are Iodine, ninhydrin, silver nitrate, or cyanoacrylate esters. The processinvolves fuming, spraying, brushing, or dipping the object in a solution of thechemic al. Yet another way to make fingerprints visible is to use radiation. A latent print requires a suitable surface for it to be picked up. Porous surfaces such as unpainted wood and some kinds of paper are unlikely to yield a useful impression. Smooth surfaces like glass, enamel, and glossy paper are ideal to lift the print if you are lucky enough to get it. Bibliography: