Hines, J.
(After stating the foregoing facts). The plaintiff in error contends that the contract, which the plaintiff seeks to have specifically performed, can not be enforced, (1) because the offer by the plaintiff was not accepted by her absolutely and unequivocally, but was changed before acceptance by her, was not accepted by the defendant, and was therefore not binding on the latter; (3) because the parties to said contract never agreed to the same, at the same time and in the same sense, their minds not meeting; (3) because the offer was to be accepted by her beforé the end of April 30, 1930, and, having been changed, no acceptance thereof as altered was ever made during the'time limit fixed therein; (4) because the original contract of sale was in writing as required by the statute of frauds, and, having been changed, was never ratified in writing by the purchaser, and therefore was never a binding contract; (5) because the alleged verbal ratification thereof by the purchaser was not made in the time limit fixed by the contract; (6) because this contract, not having been ratified in writing by the purchaser, was a unilateral one, not binding alike on *448each of the parties, the purchaser being at liberty to reject the same if she wished; (7) because the contract, not being ratified in.writing by the plaintiff, was merely a verbal contract for the sale of land, and hence is void under the statute of frauds.
The plaintiff made an offer in writing to buy from the defendant the Fraser Apartments in the city of Atlanta. This offer was signed by the plaintiff through an agent. This agent was not authorized by the plaintiff in writing to execute in her behalf this written offer. The defendant declined to accept this offer upon the terms therein set out, when presented to her by the real-estate agent who was negotiating this sale; but she agreed to accept the same, if the plaintiff would agree to pay the second loan of $4,000 on this property in January, 1921. This offer, when originally executed, contained this provision, to wit: “ Assumption of a loan due in about a year and a half, at 8%, $4,000.” The real-estate agent then struck from said provision the words “a year and a half,” and inserted in lieu thereof the words “ January, 1921.” The plaintiff then signed the written acceptance of this offer as thus changed. Thereupon the real-estate agent telephoned to the plaintiff’s son that he had made this change. The son communicated this information to his mother, who verbally confirmed and ratified this change._ Will a court of equity decline to decree specific performance of this contract, against any of the grounds of attack thereon which are - fully set out above? •
1. Under our statute of frauds any contract for the sale of lands, to be binding upon the promisor, “ must be in writing, signed by the party to be charged therewith, or by some person by him lawfully authorized.” Civil Code, § 3222. Under this statute, if the contract of sale is otherwise sufficient, and is assented to by him to whom the proposition has been made, the contract is consummated by the meeting of the minds of the two parties, and the evidence necessary to render it valid and capable of enforcement is supplied by the signature of the party sought to be charged by the offer to sell or to buy. Ullsperger v. Meyer, 217 Ill. 262 (75 N. E. 482, 2 L. R. A. (N. S.) 221); Curtis v. Blair, 26 Miss. 309; Willis v. Ellis, 98 Miss. 197 (53 So. 498, Ann. Cas. 1913A, 1039); Mason v. Decker, 72 N. Y. 595 (28 Am. R. 190); Lee v. Cherry, 85 Tenn. 707 (4 S. W. 835, 4 Am. St. R. 800); *449Bailey v. Lieshman, 32 Utah, 123 (89 Pac. 78, 13 Ann. Cas. 1116); Woodruff v. Woodruff, 44 N. J. Eq. 349 (16 Atl. 4, 1 L. R. A. 380); Miller v. Cameron, 45 N. J. Eq. 95 (15 Atl. 842, 1 L. R. A. 554); Johnston v. Tripp, 33 Fed. 530.
The general rule is that the memorandum need only be signed by the party against whom the contract is sought to be enforced. If a contract for the sale of lands is signed by the vendor alone, who is the party seeking to enforce the same, it will not be sufficient to bind the purchaser who has not signed the same. The same is true where the contract is signed by the buyer only, and he seeks to enforce the contract against the vendor. If a contract is duly signed by the vendor, it is not a good objection that it was not signed by the purchaser who is seeking to enforce the contract. If a contract for the sale of lands is signed by the purchaser, it may be enforced by the seller, though not signed by him; and vice versa, if the contract is signed by the vendor it may be enforced against him by the purchaser, though not signed by the latter. 25 B. C. L. 669, 670, 671, 672, §§ 305, 306, 307, 308; 1 Williston on Contracts, § 586. This court has stated the rule thus: “If a contract for the sale of land, required by the statute of frauds to be in writing, is evidenced by a writing signed by one party only, but sufficient to charge the party signing, such party would be bound to perform the contract. While in such a contract there is want of mutuality of obligation, still if the party in whose favor the writing is executed, though not bound because it is not signed by him, sees proper to waive his right to insist upon the invalidity of the contract, and as evidence of such waiver files a proceeding in a court of equity to enforce it, thus affirming in writing his willingness to be bound by the stipulations in the contract, he will by such proceeding, though previously not bound, put himself under the obligation of the contract. The contract then ceases to be unilateral; for by the act of the party who was in no way originally bound by the writing the contract becomes mutual, and the other party is thereby enabled to enforce it against him.” Perry v. Paschal, 103 Ga. 134, 137 (29 S. E. 703); Linton v. Williams, 25 Ga. 394; Talley v. So. Real Estate &c. Co., 152 Ga. 277 (109 S. E. 497). This disposes of most of the objections urged against the validity of this contract. The contract is sought to be enforced against the defendant who signed it. *450The original offer may not have been valid under the statute ot frauds, because it was executed in behalf of the principal by an agent not duly authorized in writing to sign the same; but this defect is waived by the plaintiff in bringing her suit for its specific performance. After the offer was changed by an agent at the direction of the plaintiff, in order to meet the requirements of the defendant, the lack of proper authority of the agent to make such change has likewise been waived by the plaintiff in bringing this suit. Acceptance by the plaintiff of the contract as thus changed need not have been in writing. 25 B. 0. L. 674, § 311. When this change was made at the instance of the defendant, and she thereafter accepted in writing the offer as made, it was tantamount to a counter-offer by her to the plaintiff, and its acceptance by the latter need not have been .in writing. When this change was made at the instance of the defendant, and she thereafter accepted the contract as changed, she is estopped from denying its validity. When the contract thus changed was presented to the defendant for acceptance, as embodying the terms upon which the plaintiff could buy this property, and she accepted the contract thus changed, the minds of the parties met, both agreeing to the same thing, at the same time. So none of the objections urged by the defendant to the validity of this contract are well taken.
2. The offer of the buyer must be accepted by the seller unequivocally, unconditionally, and without variance of any sort. There must be the mutual assent of the parties, and they must assent to the same thing in the same sense. Robinson v. Weller, 81 Ga. 704 (8 S. E. 447); Harris v. Amoskeag Lumber Co., 97 Ga. 465 (25 S. E. 519); Gray v. Lynn, 139 Ga. 294 (77 S. E. 156); Phinizy v. Bush, 129 Ga. 479 (59 S. E. 259). So when this offer by the plaintiff to purchase this property from the defendant was made, the latter must have accepted the same unconditional^, in order to bind the plaintiff. She could not in her acceptance have changed the terms thereof, or added new terms thereto. But when she rejected the original offer and signified her willingness to sell if a material alteration was made in the original offer, and this was done at her request, and she then accepted the offer as changed, such acceptance was an unconditional and unequivocal acceptance, which would bind the defendant.
3. It is urged that the verdict is contrary to the law and evi*451deuce, because the plaintiff did not make an unconditional tender of the cash payment which she was to make to the defendant under this contract, and of the notes which she was to give to the defendant for the deferred payments. Generally, in order to entitle the plaintiff to the specific performance of a contract for the purchase of land, the purchaser must make an unconditional tender of the purchase-money due, and of properly executed notes for deferred payments of the purchase-price, as called for by the contract of purchase. DeGraffenreid v. Menard, 103 Ga. 651 (30 S. E. 560); Elder v. Johnson, 115 Ga. 691 (42 S. E. 51); Terry v. Keim, 122 Ga. 43 (49 S. E. 736); Grace v. Means, 129 Ga. 638 (59 S. E. 811); Martin v. Thompson, 141 Ga. 31 (80 S. E. 318); Burkhalter v. Roach, 142 Ga. 344 (82 S. E. 1059). But tender by the vendee before suit is excused if the vendor, by conduct or declaration, proclaims that, if a tender should be made, acceptance would be refused. Miller v. Watson, 139 Ga. 29 (76 S. E. 585); Burkhalter v. Roach, supra. It appears from the evidence in the record that the defendant. declined to comply with her contract of sale, unless the plaintiff complied with certain terms not embraced in this contract; and this conduct on the part of the defendant would excuse the plaintiff from making the tender in accordance with the terms of the contract. Equity never requires a party to do a vain or useless thing before undertaking to assert his rights.
4. The plaintiff demurred to the answer of the defendant, upon the grounds fully set out in the statement of facts. The court overruled this demurrer, to which ruling the plaintiff filed her exceptions pendente lite, and she assigns error in this court thereon. In her petition the plaintiff alleged that she had made an unconditional tender of the cash payment on' the purchase-money and of the notes required in this contract. In her answer as amended the defendant denied the making of an unconditional tender, and alleged that this tender was conditioned on her accepting the agreement of the plaintiff to pay off and discharge the Ayer loan, on April 28, instead of January, 1921. This raised an issue of fact to be tried by the jury; and for this reason, if for no other, the court did not err in overruling the plaintiff’s demurrer, which was aimed at the whole of the answer.
5. Movant insists that the court erred in giving to the jury *452four instructions. In the first of these charges the judge instructed the jury that if the contract of sale, signed by the plaintiff, was changed by Dodd, the agent conducting the negotiations, and if this change was communicated to the buyer, who assented thereto, this would constitute a ratification of the change, which vrould make the contract, so signed by the defendant, binding on the plaintiff, as if the change had been made before she signed; that it would not be necessary for the plaintiff to execute a new writing ratifying the act of the agent in making this change; and that her ratification could be by word of mouth and by her acts and conduct after she was informed of the change. We are not called upon to say whether this instruction embraces a correct statement of the law in reference to the ratification of this change made by the agent in this contract and its binding force on the maker, if it had been sought to enforce this contract against her; but, if erroneous, it did no harm to the defendant. The defendant was the party to be charged, and, as we have stated above, she would be bound by this contract as changed'after she signed the same.
In another instruction the court charged the jury that if in this transaction Dodd was acting for both parties, and had authority from the plaintiff to purchase this apartment house on the terms set out in the contract of sale as originally drawn, then Dodd as the agent of the plaintiff had authority to make the change in the contract before it was signed by the defendant, that such change made by him would bind the plaintiff, and that therefore the contract, when signed by the defendant, would be binding upon both parties. Again expressing no opinion upon the question whether the plaintiff would be bound by this change, when made by the agent on her oral authority only, if suit had been brought thereon by the defendant to charge her, still it is not erroneous as to the defendant, as a finding that the defendant is bound by this contract is demanded as a matter of law.
Complaint is made of the charge of the court upon the subject of tender. On this subject the court instructed the jury, that, if the tender was made without any condition except a request that the defendant comply with the terms of the contract of sale, the plaintiff would be entitled to a verdict for specific performance. It is alleged that this instruction was error, because the terms of *453the contract were in dispute, and the court did not instruct the jury what the contract of sale was, or what its terms were. There is no merit in this ground of objection to this charge. In passing we may say that this instruction was not entirely correct. A tender must be certain and unconditional, except for a receipt in full or delivery of the obligation. Civil Code, § 4322. . This court has held that tender of the balance due on the purchase-money of land by the vendee, coupled with a condition that the vendor make and deliver to the vendee the conveyance called for by the bond for title, was not a valid and lawful tender. DeGraff enreid v. Menard, supra: Elder v. Johnson, supra; Morris v. Continental Ins. Co., 116 Ga. 53 (42 S. E. 474); Terry v. Keim, supra; Smith v. Tatum, 140 Ga. 719 (79 S. E. 775); Martin v. Thompson, supra; Burkhalter v. Roach, supra.
A tender, coupled with the condition that the vendor comply with the terms of sale, was not an unconditional tender. Of course tender by the vendee before suit will be excused if the vendor, by conduct or declaration, evinces an intention that a tender, if made, would be refused. Burkhalter v. Roach, supra.
The last exception is to this instruction: “ In construing this contract, it is the duty of the jury and of the court to so construe it as to bind both parties, where circumstances show their intention to be bound.” It is alleged that this is error, for the reason that it is the duty of 'the court to construe this contract, and that to instruct the jury that it was their duty to construe it so as to bind both parties misled the jury. This instruction was not entirely accurate. The construction of a contract is a question for the court, unless some matter of fact is involved, such as the reading of an obscurely written word and such like things, which a jury must solve. Code § 4265. The court meant to tell the jury that the construction which will uphold a contract is to be preferred. Civil Code, §4268 (3). But this inaccuracy would not require the grant of a new trial; as the court properly. construed this contract, and as the plaintiff, under the facts in the record, is entitled to a decree for specific performance.
6. The jury rendered this verdict: “ We, the jury, find for the plaintiff and for specific performance; and we further find plaintiff is entitled to receive rents due from May 8, 1920, in the amount of $2,205.93, less operating expenses covering same pe*454riod.” Tlie defendant excepts to this verdict, on the ground that it was the evident intention of the jury to reduce the amount of the money finding in favor of the plaintiff by some amount, which can not be ascertained from anything in the evidence or pleadings, and that for this reason it is void for vagueness and uncertainty. Is this verdict void for uncertainty? It is impossible to tell what amount the jury intended to allow the plaintiff as rents, as the gross sum of $2,205.93 was to be reduced by the expenses of operating this apartment from May 8, 1920, to the date of the verdict; and the part of the verdict finding a money verdict in favor of the plaintiff can not be upheld, for lack of certainty. Whitley v. Baggett, 104 Ga. 22 (30 S. E. 428). But it is insisted that the language, “ less operating expenses covering the same period,” for which rent was allowed, may be stricken as surplusage. This can only be done where superadded words are meaningless. N. & S. St. R. Co. v. Crayton, 86 Ga. 499 (12 S. E. 877). In the last-cited case the language, “less freight,” was treated as surplusage, because freight was not included in the controversy in that case. It is true that all surplusage in a verdict may be disregarded. “ The maxim, ‘ utile per inutile non vitiatur,’ saves ” verdicts “ from the taint of any ambiguity or uncertainty brought about by rejectable surplusage.” Peninsular Naval Stores Co. v. State, 20 Ga. App. 501 (93 S. E. 159). We can not say that the matter of the expenses of operating these apartments was not involved in this controversy. Plaintiff prayed for a receiver to collect the rents of these apartments, and to apply these rents to payment of the interest on the loans on the property, insurance, and taxes; and prayed that the rents be given her from the date of her tender on May 8, 1920. She must mean by this the net and not. the gross rents, as it is a matter of common knowledge that the gross rents of apartments are reduced by the expenses of operating them, including such items as wages of janitor, water and light rates, cost of coal, and such things.
A new trial is granted solely on the ground that the verdict is void for uncertainty in finding for the plaintiff a sum for rents, less expenses of operation, without fixing the amount of these expenses; but direction is given that the verdict for the plaintiff for specific performance stand, and that the next trial be confined to an accounting, as we are authorized to do under the Civil Code, *455§ 6805, with costs against the defendant in error.
Judgment reversed m part, and affirmed in part, with direction.
All the Justices concur.