Properly construed, count 1 of the petition clearly stated a cause of action for the unpaid balance due on the alleged promissory note. It is alleged that the defendant is indebted to the plaintiff in the sum of $850
plus interest
*548
thereon at eight percent
from October 15, 1950, the date of the last payment made on the note, and the plaintiff in his prayer asks that interest at eight percent be awarded to him. Code § 57-101 provides that any rate of interest higher than seven percent must be specified in writing. Obviously, if the plaintiff is to obtain interest at eight percent he must sue upon the note, the written instrument providing therefor. Tréating count 1 as a suit upon the note, we are confronted then with the question of whether or not the court erred in sustaining the special demurrer requiring the plaintiff to attach a copy of the note to his petition. In
Edwards
v.
Camp,
29
Ga. App.
556 (
Since count 1 of the petition is properly construed to constitute an action on the note and not upon the rentention-of-title *549 contract, it was unnecessary to attach a copy of that contract to the petition. East Atlanta Land Co. v. Mower, 138 Ga. 380 (2) (75 S. E. 418); Reed v. Colonial Hill Co., supra. The trial court, therefore, erred in sustaining the special demurrer to paragraph 7 of count 1.
“A suit upon a contract for purchase-money due by instalments may be maintained for the amount of such instalments as were due at the institution of the suit, but not for instalments to become due.”
McDonald
v.
Rimes,
137
Ga.
732 (
As to count 2 of the petition, the trial court did not err in sustaining the oral motion to dismiss, in the nature of a general demurrer. There cannot be an express and implied contract for the same thing existing at the same time between the same parties. It is only when the parties themselves do not expressly agree, that the law interposes and raises a promise; and no agreement can be implied where there is an express one existing. While it is alleged in this count that the plaintiff sold the automobile for the sum of $1300, and delivered it on October 15, 1949, from which the law would ordinarily imply a ¡oromise to pay, nothing more appearing, it is also alleged that the defendant promised to pay for the automobile in monthly instalments of $50 each. As a matter of mathematical calculation the defendant under such agreement had 26 months within which to make the payments in the absence of an agreement that failure to make a monthly payment would cause the remaining instalments to become due and payable. There are no allegations of abandonment or rescission of this arrangement as to payments, nor allegations from which abandonment or
*550
rescission could be inferred; and with the express agreement as to the payment of the purchase price still outstanding the plaintiff cannot recover upon a quantum valebat.
It follows, therefore, that the trial court erred in sustaining the demurrers to count 1 of the petition, but was correct in sustaining the general demurrer to count 2.
Judgment affirmed in part and reversed in part.
