Quinine side effects include deafness, low blood platelets, and an irregular heartbeat. Use can make one more prone to sunburn. While it is unclear if use during pregnancy causes harm to the baby, use to treat malaria during pregnancy is still recommended. Quinine is an alkaloid, a naturally occurring chemical compound. How it works as a medicine is not entirely clear. Quinine was first isolated in 1820 from the bark of a cinchona tree. Bark extracts have been used to treat malaria since at least 1632. It is on the World Health Organization's List of Essential Medicines, the most effective and
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