Serges owned a retail butcher shop. One of his managers borrowed $3,500 from David for use in the butcher shop. Serges claimed that the manager had no authority to borrow money. Nevertheless, Serges made payments of $200. Serges also told David on several occasions that the full sum would eventually be paid. Was Serges liable? (David v. Serges, 373 Mich. 442, 129 N.W.2d 882)