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
Bark hack The first sentence is basically correct except that the blade is straight rather than curved. With the bark hack, only the bark is removed; it does not cut into the wood as the wood hack did. The wood hack was used up until the early 1950's and the trees were "chipped or streaked" each week during the sap flow season. With the bark hack, only the bark was removed and a 50% sulfuric acid solution was sprayed on the "streak" and it had to be done only every 2 weeks. Bark hack A bark hack is a tool used to