Numbers 5:23

And the priest shall write these curses in a book,.... The above curses imprecated on herself by an oath; the words and the letters of them were written at length, in a scroll of parchment; and, as some say also, her name, but not her double amen to them y:

and he shall blot [them] out with the bitter water: wash them out with it, and into it, or scrape them off of the parchment into it.

y Misnah, ut supra, (Sotah, c. 2) sect. 3.