Barnes, J.
Eor the sake of brevity the two Trzebiatow-skis will be referred to by their Christian names. Charles was authorized to collect the interest on the note in suit, but not the principal. When Malloy learned what had been done *248lie might have disaffirmed the acts of Charles and looked to the plaintiffs for the full amount of the note, or he might have elected to affirm and ratify such acts and treat the estate of Charles as his debtor for the amount of the principal collected. It was six or eight months after Malloy knew that the payments had been made to Charles before he advised the plaintiffs that he would look to them for the amount so paid. Malloy knew that the plaintiffs paid the interest to Charles during his lifetime and continued to pay it to Albert after Charles’s death. He was in Albert’s office on one occasion when plaintiffs made a payment on the principal to Albert and did not then make any objection, except to tell Albert that he should not have demanded the money. He received three separate payments on principal from Albert. He also received from him interest paid by plaintiffs on the $900 which they admitted to be due. Albert paid out of his own funds or out of the proceeds of the estate of Charles the interest on the $700' collected by Charles, when such interest became due under the terms of the note. Malloy demanded of Albert payment of the amounts which Charles had collected, according to Albert’s evidence, which the court finds to be true in the opinion rendered in the case. Such demand could only be made on the theory that Malloy chose to consider the estate of Charles his debtor for the moneys collected. Interest on the amounts collected by Charles could only be demanded of Albert on the same theory. We have (1) the fact that Malloy did not advise the plaintiffs that Charles had no right to collect the principal on the note until six or eight months after he knew that the collections had been made; (2) the fact that a demand was made on Albert, who was the administrator of his brother’s estate, for the amount of principal collected by Charles; (3) the fact that for a considerable period of time interest was collected semi-annually from Albert on the $700 principal which Charles had collected. These facts in connection with other less persuasive ones heretofore referred to warranted the court in finding *249that Malloy elected to ratify the acts of Charles in receiving payments on the principal.
When an agent acts in excess of the authority conferred upon him, and the person for whom he has undertaken to act is fully notified of what has been done, it becomes the duty of the principal to either affirm or disaffirm the act of the supposed agent within a reasonable time after such notice or he is bound by such act. McWhinne v. Martin, 77 Wis. 182, 187, 46 N. W. 118; Saveland v. Green, 40 Wis. 431; Gold M. Co. v. National Bank, 96 U. S. 640. Numerous other cases to the same effect will be found cited in 31 Cyc. 1275, and 40 Cent. Dig. tit. Principal and Agent, § 641.
The receipt of interest payments from the administrator of Charles’s estate might well show ratification in itself. 31 Cyc. 1265; Very v. Levy, 13 How. 345. Reinforced as it is by the other significant facts referred to, the trial court’s decision is well supported by the evidence.
By the Court. — Judgment affirmed.