Numerous errors are assigned by the appellants. The first error assigned, that the complaint did not state a cause of action, might, we think, have been properly overruled, but if there was any defect in the complaint it *215was clearly the duty of the court to permit an amendment, as was done. The case had been tried upon its merits, and it would have been a perversion of justice to have turned the plaintiff out of court for want of some formal or technical allegation in his complaint.
The second class of errors alleged are those which it is claime d were committed by the court in permitting parol proof as to the terms of the contract, against the objection of the appellants, after it appeared that the contract between the parties was in writing. If the court below committed any errors in this respect, they could not have prejudiced the appellants, for the reason that the court afterwards submitted the case to the jury upon the theory that the written contract given in evidence on the trial should determine the rights of the parties. And if the construction given to the written contract by the court is its true construction, then there is no material difference between the parol contract set out in the complaint, and which was permitted to be proved on the trial, and the written contract which the court instructed the jury should be the basis of the rights of the respective parties. The written contract being in evidence before the court and jury, as well as the parol contract, if the two contracts are alike in all material respects it could not prejudice the 'appellants that the respondent was permitted to prove the contents of the written contract by parol evidence.
The learned circuit judge construed' the written contract to mean that the balance of the wood, after the first cargo, was to be delivered at intervals of a week or ten days, and that consequently after delivering one cargo, which was accepted and paid for by the respondent, the appellants were not at liberty to tender another cargo within a week after the delivery and acceptance óf the first cargo. This ruling becomes material upon two questions: First, whether the refusal to accept, receive, and pay for the cargo of forty *216cords tendered to the- respondent on the contract was a breach of the contract on his part; and, second, upon the question of damages. We are inclined to hold that the written contract ought to be construed as the learned circuit judge construed it. It seems to us that it is clear that it was not the intent of the parties that the whole 500 cords might be delivered or tendered to the respondent at the same time or on the same day. It provides, in terms, that the first cargo shall be shipped in ten days or two weeks from the date of the order; the balance to follow in cargoes a week or ten days between, so as to have it convenient to handle the same at respondent’s dock; and the words, “if convenient to ship,” and “can do so as well” do not make it optional with the appellants to deliver the whole 500 cords in cargoes on the same day or on consecutive days. Such a construction would either give no effect to the words, “ the balance to follow in cargoes a week or ten days between, so as to have it convenient to handle here,” or else those words must be held to have been inserted in the contract for the sole convenience of the appellants. That they were inserted simply for the convenience of the appellants is negatived by the words, “so as to have it convenient to handle here.” These words evidently refer to the convenience of the respondent in receiving the wood. It would seem that the appellants, when they drew their answer, so construed the contract, otherwise they would not have alleged (against the fact) that the second cargo of forty cords was tendered on or about October 26, 1880, ten days after the delivery of the first cargo.
- Holding that the learned circuit judge properly construed the written order for the wood, there was no breach of the contract on the part of the respondent by refusing to receive the forty cords of wood tendered after the delivery and acceptance of the first cargo of 105 cords, the same having been tendered on the same day of the delivery of the 105 *217cords. The evidence shows that this forty cords was not intended to be delivered on this contract when shipped by the appellants, but was tendered because it had missed its destination by reason of a storm, and then offered to respondent on his contract, as a convenient method of disposing of the same by the appellants. The tender, under the circumstances, can have little weight as evidence tending to show that the appellants understood that by the terms of their contract they were at liberty to tender a second cargo, or all the balance of the wood, after the first cargo, immediately and without the lapse of any definite period of time between the delivery of the several cargoes which were to make up the 500 cords.
. Construing the contract, as it was construed by the learned circuit judge, viz., “ that the wood was to be delivered in cargoes, and that after the first delivery, a second could not be made until the lapse of at least one week, and must be delivered wfithin ten days, and so of the subsequent cargoes until all was delivered,” the only other important question in the case is, whether the rulings of the court upon the subject of damages were correct. The learned circuit judge, after having determined that the contract between the parties was that the 500 cords of wood was to be delivered in cargoes, the first cargo to bé.delivered within ten days or two weeks after the date of the contract, and the balance in cargoes at intervals of not less than one week or more than ten days, substantially held that there was no breach of the contract on the part of the appellants until November 19, 1880, when they notified the respondent that they did not intend to deliver any more wood upon the contract for reasons stated. In this we think the learned circuit judge erred. , It is very clear to us that, upon the construction given to the contract between the parties, when the appellants failed to deliver a second cargo of wood October 26, 1880, there was a breach of the contract as to the cargo they *218ought to have delivered on or before that day; and when they failed to deliver another cargo November 5,1880, there was another breach of the contract on the part of the.appellants as to the cargo which was then due on the contract; and so a failure to deliver another cargo November 15th would be another breach, if it required a third cargo or more to fill the contract for the 500 cords.
The damages to be assessed upon the breach of a contract of sale by the seller is, as a general rule, where the purchaser has not paid in advance the purchase price, the difference between the contract price of the articles sold and the market price at the time and place of delivery. One of the exceptions to this rule, which it is claimed by the respondent is applicable to the facts of this case, is that when the articles purchased are purchased for a specific purpose, and such purpose is made known to the seller at the time of making the contract, special damages resulting from the inability of the purchaser to carry out such purpose by reason of the breach of the contract, may be recovered. See Shepard v. Milwaukee Gas Light Co., 15 Wis., 318, 327; Richardson v. Chynoweth, 26 Wis., 656; Chapman v. Ingram, 30 Wis., 290; Candee v. W. U. Tel. Co., 34 Wis., 471; Hammer v. Schoefelder, 47 Wis., 455; Cockburn v. Ashland Limber Co., 54 Wis., 619, 626. The rule is very accurately stated by the learned counsel for the respondent in their brief, where they say, “Certainly the plaintiff was entitled to recover the value of the wood on the days when it should be delivered.”
When the contract is for the sale and delivery of personal property, to be delivered in instalments at fixed times, the failure to deliver any instalment at the time agreed upon is a breach of the contract, and there can be no doubt but that the purchaser could maintain an action for such breach without waiting until the time for the delivery of the last instalment had passed, and the purchaser’s damages for such breach must be ascertained in the same manner and upon *219the same principles of law as "though there were no other breaches of the contract on the part of the vendor. The rule is stated by Sedgwick, in his work on the Measure of Damages, as follows: “Where delivery is required to be made by instalments, the measure of damages will be estimated by the value at the time each delivery should be made. So, where a contract is for the delivery of goods in equal proportions, in a given number of months, and the action for non-delivery is brought after the period stipulated for the last delivery, the proper measure of damages is the sum of the differences between the contract and the market prices on the last day of each month respectively.” 1 Sedgw. on Dam. (7th ed.), 558, note; Brown v. Muller, L. R. 7 Exch., 319; Missouri Furnace Co. v. Cochran, 8 Fed. Rep., 463; Roper v. Johnson, L. R. 8 C. P., 167; Ex parte Llansamlet Tin Plate Co. (In re Voss), L. R. 16 Eq., 155; Tyers v. Rosedale & F. I. Co., L. R. 8 Exch., 305; Boorman v. Nash, 9 Barn. & C., 145, 152; Frost v. Knight, L. R. 7 Exch., 111.
In this view of the case, the learned circuit judge erred in excluding the evidence offered by the appellants, tending to show the market value in Racine of wood of the kind mentioned in the contract, in the months of October and November, and in ruling that the evidence must be confined to its value on and after November 19, 1880; and also in excluding evidence tending to show that the plaintiff could, with reasonable diligence, have purchased the cargoes which should have been delivered October 26th, and November 5th and 15th, in the market at the same price he had agreed to pay the appellants.
Eor the breaches of the contract which occurred previous to November 19th, it is clear that the respondent could recover only the difference between the market price and the contract price at the time when the cargoes due before that date should have been delivered, unless it was shown that the respondent could not obtain any wood in the mar*220ket to make good the cargoes which the appellants failed to deliver upon the contract at the times fixed therein. Under the construction given to the contract, it is clear that the appellants could not have compelled the respondent to receive the cargoes due after the dates at which they were to be delivered by the terms of the contract, or have recovered damages of him. for a refusal to receive the same after such dates. It would seem to be equally clear that the respondent cannot wait until the time for the delivery of the last instalment had passed and then insist that the breaches of the contract shall all be deemed to have taken place on such last day for the purpose of assessing his damages.
In order to fix the amount of damages the respondent may be entitled to recover for the non-delivery of the several cargoes at the times agreed upon, it will be necessary to determine from the evidence how many cords of wood constitute a cargo under the contract. The contract does not in terms determine that question, and it must be ascertained by evidence showing what the intent of the parties was upon that subject. We have no means of determining that question from this record. If upon a new trial the evidence shall show that the respondent could not have purchased the wood from other parties by the use of reasonable diligence, to supply the place of the wood which the appellants should have delivered upon their contract, at the times the same should have been delivered, or at any time thereafter, for use in his business during the winter of 1880-1881, then we are of the opinion that the circuit judge gave the proper rule of damages in the last paragraph of his charge to the jury, changed as below, viz.: “ That the measure of damages is the difference between the contract price and what the wood was actually worth on the plaintiff’s dock at the times when the same should have been delivered under the contract, to be sold by him in the course of his business.”
By the Court.— The judgment'of the circuit court is reversed, and the cause remanded for a new trial.