Tree from the cinchona tree ("Cinchona") and was for a long time the remedy of choice for the treatment of malaria. Aspirin was synthesised to replace the sodium salicylate derived from the bark of willow trees ("Salix") which had unpleasant side effects. The anti-cancer drug Paclitaxel is derived from taxol, a substance found in the bark of the Pacific yew ("Taxus brevifolia"). Other tree based drugs come from the paw-paw ("Carica papaya"), the cassia ("Cassia spp."), the cocoa tree ("Theobroma cacao"), the tree of life ("Camptotheca acuminata") and the downy birch ("Betula pubescens"). The papery bark of the white birch tree
Northern Hemisphere to draw air toward it in a counter-clockwise pattern. Hurricanes and tropical storms (massive low-pressure systems) spin counter-clockwise in the Northern Hemisphere. The shadow of a sundial moves clockwise in the Northern Hemisphere (opposite of the Southern Hemisphere). During the day, the Sun tends to rise to its maximum at a southerly position except between the Tropic of Cancer and the Equator, where the sun can be seen to the north, directly overhead, or to the south at noon dependent on the time of year. When viewed from the Northern Hemisphere, the Moon appears inverted compared to a view from