¶1delivered the opinion of the Court.
¶2There must be a new trial in this case. It was erroneous to permit the defendants to prove the account *48offered as a set-off, under tbe book debt law. The account is for articles delivered to the plaintiffs to sell on commission, and not for goods sold and delivered. The act of 1756 only applies to the latter case, and does not embrace the former. There is no other proof of the adverse account.
¶3The defendants filed a bill for discovery, under the act of Assembly on that subject, in relation to these dealings, and the state of accounts between the parties. The interrogatories were fully answered, and the same was read in evidence by the defendants. By this proceeding the plaintiffs were made witnesses, and their statements must be taken as true, so far as they are responsive to the interrogatories propounded; and the burden of disproving them is thrown upon the defendants. This is not done, except by the affidavit of defendants to their account, and this, we have seen, is inadmissible.
¶4The suit is brought upon a note for $115.80. The credits admitted in the answer to the bill of discovery, are about $80. No other credits are proved, and still the judgment is in favor of defendants, on their plea of set-off, for $37.50.
¶5The judgment must be reversed.