— The principle is rudimentary that as between principal and agent the authority of the latter is revocable at any time if not coupled with an interest. The authority of the agent to represent the principal depends upon the will and license of the principal. It is the act of the principal which creates the authority; it is for his benefit and to subserve his purposes that it is called into being; and, unless the agent has acquired with the authority an interest in the subject-matter, it is in the principal’s interest alone that the authority is to be exercised. The agent has no right to insist upon a further execution of the authority if the principal desires it to terminate. It is a general rule that as between principal and agent the authority of the latter may be revoked by the former at his will at any time and with or without reason therefor, except where the agent’s authority is coupled with an interest." Mechem on Agency, sec. 204; State *313ex rel. v. Walker, 88 Mo. 279; Hunt v. Rousmanier, 8 Wheat. 201.
The exceptions to the general rule just stated is where the power is given as a part of a security or for a valuable consideration, or where the power is coupled with an interest. But the interest in such cases is an interest in the subject-matter on which the power is to be exercised. An interest in that which is produced by the exercise of the power is not sufficient. The power must be engrafted on an interest in the property on which the power is to be exercised, and not an interest in the money derived from the exercise of the power. Hunt v. Rousmanier, supra; Barr v. Schroeder, 32 Cal. 609; Coffin v. Landis, 46 Pa. St. 431; Blackstone v. Battermore, 53 Pa. St. 266. And so it has been held that a power to collect money and receive property and to sell and convey the property of the principal, the agent to receive one-half of the net proceeds as compensation, is not a power coupled with an interest and is revocable. Hartley’s Appeal, 53 Pa. St. 212.
In this case, the defendants who had lately been copartners, engaged in the practice of medicine, entered into a parol contract with plaintiff who was an attorney, whereby it was agreed that the defendants would turn over to plaintiff their books of account for collection and adjustment, and for which the former would pay the latter as a compensation for his services ten per cent, on all sums collected, and five per cent, on all accounts adjusted by note. The defendants refused to deliver their books of account to plaintiff, and so did not carry out the contract. This, the defendants could do, and on account of which, the plaintiff has no legal ground of complaint.
Of course, where the principal has the power to revoke the authority o'f the agent, he may, neverthe*314less, subject himself to a claim for damages if be exercise such power contrary to bis agreement.
Tbe evidence does not show that tbe plaintiff’s employment was fixed for any’ period of duration. Tbe written admission of one of tbe defendants offered in evidence by plaintiff showed no more than that plaintiff was to “try and have all notes and accounts adjusted in., eighteen months.” Tbe duration of tbe contract was contingent and uncertain. It might have been performed by plaintiff in a week, a month or year.. So it has been held that an appointment of an agent to' do certain acts during a given period does not, of itself,, amount to an agreement that be should be permitted to continue to act- during that period. Meebem on Contracts, sec. 211. In any view which we have been able to take of the case, we are unable to find that the court below erred in sustaining the demurrer to the-plaintiff’s evidence.
It follows, therefore, that the judgment will be,affirmed.
All concur.