Quinine London. It remained the antimalarial drug of choice until the 1940s, when other drugs took over. The form of quinine most effective in treating malaria was found by Charles Marie de La Condamine in 1737. In 1820, French researchers Pierre Joseph Pelletier and Joseph Bienaimé Caventou first isolated quinine from the bark of a tree in the genus "Cinchona" - probably "Cinchona officinalis" - and subsequently named the substance. The name was derived from the original Quechua (Inca) word for the cinchona tree bark, "quina" or "quina-quina", which means "bark of bark" or "holy bark". Prior to 1820, the bark
Bark pocket indicator of air pollutants during which the time they formed. They can be used to monitor heavy metals such as lead and copper, as dust or other matter deposited on the bark at the time of formation is still present. One study analysed the amount of polycyclic aromatic hydrocarbons (PAHs) present in bark pockets as a historical record of air quality, possible due to the interaction between PAHs and lipids in the bark. Bark pocket Bark pockets can be formed by inosculation, formation of a tree fork, encapsulation of a branch, joining together of an uneven trunk, or encapsulation of