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
Birch bark the phloem, kills the tree by preventing the flow of sap to the roots. To prevent it from rolling up during storage, the bark should be spread open and kept pressed flat. Birch bark can be cut with a sharp knife, and worked like cardboard. For sharp bending, the fold should be scored (scratched) first with a blunt stylus. Fresh bark can be worked as is; bark that has dried up (before or after collection) should be softened by steaming, by soaking in warm water, or over a fire. Birch bark was a valuable construction material in any part of