Sizing is a type of waterproofing. Unfortunately, mercury sizing to help waterproof wool hats, was made more effective by being less water soluble and more fat soluble. Mercury thus compounded, is a recipe for disaster, since the alkyl and arylated mercurials are far more fat soluble, far more difficult to excrete, and far more likely to cause mental and other health problems. Hair analyses of civil war veterans might provide some interesting forensic clues as to how much of the “Civil War insanity” was caused by simple mercury or gold poisoning.