Arthur Eichengrün the invention of aspirin in 1897. Impure acetylsalicylic acid (ASA, the active compound of aspirin) had been synthesized already in 1853 by French chemist Charles Frédéric Gerhardt; the 1897 process developed at Bayer was the first to produce pure ASA that could be used for medical purposes. Due to the rise of the Nazis in Germany, Eichengrün was unable to object when Hoffman first made the claim that "he" (Hoffman) invented aspirin, in the footnote of a 1934 German Encyclopedia. Hoffman's claim was once widely accepted, but many historians now consider it to be discredited. Eichengrün first claimed to have
Willow flute tempered scale. Modern willow flutes are typically made of plastic (PVC tubing is often used), but the original willow flutes were made from sections of bark cut from green willow branches. Willow flutes could only be made this way during the spring, and became unplayable when the bark dried out. Noted modern willow flute artists include the group Hedningarna and Anders Norudde of Sweden. Other Scandinavian groups that use the Seljefløyte in traditional arrangements include Eivind Groven, Steinar Ofsdal, Groupa and Bask. There is also a Karelian variant of the willow flute that is made in Finnish Karelia and the