This is a paragraph from one of the Engines of Our Ingenuity that I have been enjoying.
www.uh.edu/engines/epi1.htm The author is a professor of engineering. So I was
surprised to find what seems to be a very obviously wrong choice of words.
"During the mid-1700s potash-making became an
American cottage industry. We used the burned-out
ashes from wood fires. We leeched them in big iron
kettles. Then we boiled the liquid and created a
potash distillate."

To me, the distillate is the water removed. What's left,the residue, is the potassium salts
and other solids. which I would call the product. I am genuinely surprised to see this author
make such a blunder. Any comments?

distilllate
n.
< L distillatus, pp. of distillare6
1 a product of distillation; liquid obtained by distilling
2 the essence of anything
Incidentally his "leech" I assume is typo for "leach".