— Defendants Darlington and Hoffman Avere sureties for Harrison on a bond executed by the latter to secure the performance of a contract to erect for plaintiffs a double two-story fiat building in the city of St. Louis, complete the job by January 15, 1903, and protect plaintiffs from demands and liens of laborers and materialmen. Plaintiffs allege they were damaged *377by Harrison’s failure to erect tbe building in a skilful and workmanlike manner in some particulars, complete it in tbe agreed time and turn it over to them free from liens. Harrison was a codefendant, but as be is no party to tbe appeal, wbicb was taken only by tbe sureties, we are not concerned with bis answer. Tbe sureties admitted tbe execution of tbe bond, but alleged plaintiffs failed to comply on their part, setting out certain breaches, none of wbicb are important, except supposed deviations from tbe contract in paying installments of tbe purchase price. As a point of practice is raised in respect of tbe refusal of the court to permit an amendment of tbe portion of tbe answer wbicb related to the payments, we will copy that part, introducing into it tbe proposed interlineations and indicating them by italics.

“Defendants state that plaintiffs failed to make tbe payments according to tbe terms of said contract, in that plaintiffs failed on each bouse to make tbe payments at tbe period and in the amounts specified in said contract; that when tbe first floor joists were laid a payment of eight hundred dollars ($800) was due, but that payment was not made until long after it was due;.that when tbe second'floor joists were laid $1,100 was due, but was not paid until long after due; that tbe payment of $1,100 wbicb Avas due when tbe gravel roof was on was not paid when dne, but withheld for a long time thereafter; that $900 was due when tbe building was ready, for plastering, and that this amount was not paid until long after due; that $1,250 was due when tbe plastering was finished, and that plaintiffs delayed payment of this amount on each building; that all the payments made by plaintiffs toere in different amounts and made at different period from that specified in the contractj that when each building was completed a payment of $2,800 was due, wbicb plaintiffs refused to pay and have never made payment to defendants Harrison; that defendants Darlington and Hoffman were not notified of these changes of tbe time of payment, and did not consent or agree to *378the delay upon the part of plaintiffs in making payment according to the contract, as the work progressed.”

The case was referred to a referee to report on all the issues of law and fact, and after his report had been filed, exceptions taken and when the argument on the exceptions was to occur, defendants requested leave to amend their answer by interlining the italicised words, and the court refused the request. The amendment was asked for because, as originally filed, the answer made defense as to this matter solely on the ground that the intermediate installments of the contract price were not paid until after they were due and the final one never was paid. The evidence regarding when the several payments occurred was contradictory, plaintiff Joseph Freasier testifying they were made slightly in advance of their maturity, and Harrison that they were delayed in every instance. The finding of the referee was as follows on this issue:

“The plaintiffs made the payment to the defendant Harrison as the work progressed, substantially at the times and in the manner called for in the contract, except the last payment, which was withheld. The first. and second payments on the west building were made under peculiar circumstances. The first payment was to be made under the contract, when the first floor joists were laid, and the second payment was to be made when the second floor joists were laid. The stone masons on the buildings failed to put in the center row of posts or pillars, upon which the first floor joists were to be supported, and the joists, for this reason, were put in without any supports. The plaintiffs claim, for this reason that the first payment was made before it was due — that the joists were not properly laid until the girder was under them. For the same reason plaintiffs contend that the second payment was made ahead of time.

“The payments by plaintiffs were usually a little more than the contract called for at the time they were *379made. At times these payments would amount to a few hundred dollars more than was due, according to plaintiffs’ contention; but according to the contentions of the defendants, plaintiffs were always behind in. their payments.

“Defendants, in their brief, especially the defendants Darlington and Hoffman, contend these advance payments by plaintiffs avoided the bond, but there is no-issue of that character made by the pleadings. Said defendants, in their answer, make complaint that the plaintiffs failed to make the payments as they became due. No charge is made in the pleadings that they made the payments in advance without the consent of the sureties on the bond. No disadvantage arose from the act of plaintiffs in making these payments in the manner they were made, nor were the defendants, Harrison, Darling-ton, and Hoffman injured or prejudiced in any manner thereby.”

The referee having found the payments were usually a little more than the contract called for at. the time they were made, and having ruled defendants had averred nothing in their answer about plaintiffs having paid before the installments were due, and without the consent of the sureties, but on the contrary had averred plaintiffs failed to pay as the installments became due, defendants sought to amend so as to adapt the answer to the referee’s finding that the payments were made in advance instead of in arrear, and yet retain the original defense of default by plaintiffs; contending either deviation from the contract would exonerate them from liability as sureties. The only question it is necessary to determine is whether the refusal to allow the amendment is reversible error. At this stage of the case the court, in its discretion might or might not permit the answer to be amended, and its decision cannot be reversed unless, under all the circumstances, it allowed plaintiffs to succeed on a technical point which might have been determined against them without prejudice to their sub*380stantial rights and in aid of the justice of the cause. [Henderson v. Henderson, 55 Mo. 534; Ensworth v. Barton, 67 Mo. 622; Joyce v. Growney, 154 Mo. 253.] It is manifest there was no abuse of discretion in the present instance, for this reason if for no other; as the answer would read if amended, it set up.no other defense regarding the payments except that they were made after due. It is true the italicised language says they were made in different amounts and at different periods from these specified in the contract; but as this language was interlined among specific averments that each payment was made after due, the effect is to state a defense based on plaintiffs’ failure to pay the successive installments when they were due — the defense first pleaded.

The judgment in favor of plaintiffs was according to- the report of the referee in every respect except a trifling item, and as it cannot be assailed unless the amendment should have been permitted, we order it affirmed.