A dictionary entry from Knight's American Mechanical Dictionary on retting, the steeping of flax or hemp to loosen the fiber from the woody core. It describes traditional water retting, grassing, and dew retting, and several 19th-century mechanical and chemical processes, including Schenck's steam-heated vat apparatus (1851), Bower's process, and ammonia or alkaline treatments. It also notes that hemp is retted much like flax.