Thomas Chapman, The Cyder-Maker's Instructor, Sweet-Maker's Assistant…
“ There is what is called a fret, which is only a partial fermentation, that nature is strong enough in some liquors to bring on, without the assistance of art; but this fret, or partial fermentation, is never strong enough to discharge the liquor of its foul parts; and if they should ever happen to subside, the least alteration in weather, as well as a hundred other accidents, will occasion their commixing, and render the liquor almost, or altogether as foul as ever; to prevent which we call in the assistance of art, and which our method will effectually prevent. ”
