Another post made me start seaching the net for some obscure laundry detergent recipe (don't know if it really exists or not, got distracted) and found this about 'bucking with lye'.
It's apparently a method of bleaching laundry (once a year or more often, not really sure) that was the norm centuries ago. Sounds sort of disgusting because besides using lye and ashes and a bucking cloth, urine or dung was also used.
Here's the
link to the article. There are links to various old-time methods for doing household things that look pretty interesting.