By the Court. A mistake in a former settlement canuot be admitted as a legal charge on book: Tbe party affected by it must have bis remedy by another kind of action. Tbe statute wbicb permits interested persons to testify in the action of book debt, is not peremptory. There may be many exceptions wherein be shall be excluded bis testimony. And wherever there appears a settlement under band, tbe court will never admit tbe parties to go over it; for it wordd open a door for great uncertainty and injustice. In tbe late case of Waldron, wbicb was an action of book debt, tbe question was, whether tbe parties might go beyond a former settlement, and it was adjudged they should not.