Willow active extract of the bark, called salicin, was isolated to its crystalline form in 1828 by Henri Leroux, a French pharmacist, and Raffaele Piria, an Italian chemist, who then succeeded in separating out the compound in its pure state. In 1897, Felix Hoffmann created a synthetically altered version of salicin (in his case derived from the "Spiraea" plant), which caused less digestive upset than pure salicylic acid. The new drug, formally acetylsalicylic acid, was named Aspirin by Hoffmann's employer Bayer AG. This gave rise to the hugely important class of drugs known as nonsteroidal anti-inflammatory drugs (NSAIDs). Some of humans'
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