Nail polish can mask damaged or disfigured nails. There are 17 principal nail polish finishes: Nail polish remover is an organic solvent that may also include oils, scents, and coloring. Nail polish remover packages may include individual felt pads soaked in remover, a bottle of liquid remover used with a cotton ball or cotton pad, or a container filled with foam into which one inserts a finger and twists it until the polish comes off. Choosing a type of remover is determined by the user's preference, and often the price or quality of the remover. The most common remover is acetone. This
Science of smells Science of smells The odorology or science of smells is a technology used mainly in criminology for judicial identification. The technology is based on the analysis of smells by dogs notably to merge the criminals or to identify the smell of objects (explosives, drugs). Olfaction of dogs is used for a long time by the police (location of drug, of explosives, of weapon, body of missing persons, criminals' identification) or the services of rescue (bodies buried under avalanches). From 1910, a dog handler Friedo Schmidt describes in his book Verbrecherspur und Polizeihund («The criminal links and the police dog») how