In an action by real estate brokers for commissions a request to charge that plaintiffs could not recover if the prospective purchasers had, in fact, and in good faith, abandoned their negotiations for the purchase through plaintiffs before the matter was taken up with the purchasers by another person, was improperly modified by adding a further condition to the defeat of plaintiffs' recovery, that plaintiffs had led defendants, through their attorney, to believe that plaintiffs had abandoned all efforts to make a sale, and had abandoned the idea of association with the transaction any further; since, to warrant a recovery for plaintiffs their services must have been the efficient cause of the sale, regardless of their abandonment of the transaction, and defendants, as well as plaintiffs, could be the moving party in the cancellation of the agency. Young v. Hubbard, 154 Mich. 218, 15 D. L. N. 725, 117 N. W. 632.