Respondent’s counsel contend that the assignments of error to impeach the judgment cannot properly affect it since there was no reply to the counterclaim contained in the answer, and respondent was therefore entitled to the judgment obtained on the pleadings. If a reply were required, under the circumstances, in order to put the allegations constituting the counterclaim in issue, it was effectually waived by respondent’s treating the same as at issue by going to trial upon the merits, and proceeding therein till near the close thereof before suggesting anything to the contrary. Killman v. Gregory, 91 Wis. 478, 65 N. W. 53; 18 Ency. Pl. & Pr. 650.
Appellant contends that the judgment is not sustained by the verdict for several reasons, which will be considered:
(a) The verdict and judgment are based on express warranty and one essential fact to sustain that, since it is undisputed that the contract on appellant’s part was made by its agent, was neither found by the jury, nor was there any evidence on the question, such fact being that such agent had authority to bind his principal by warranty.
Westurn v. Page, ,94 Wis. 251, 68 N. W. 1003, and Waupaca E. L. & R. Co. v. Milwaukee E. R. & L. Co. 112 Wis. Wis. 469, 88 N. W. 308, support counsel’s proposition as to the law, but it does not apply to this case, because the contract here was in writing, contained no express warranty, and *9tbe cause was not properly treatable upon tbe theory that there was such.
(b) The jury should have been required to determine whether certain representations claimed to have been made by the agent at the time the contract was entered into, were statements of fact or mere expressions of opinion.
We fail to see any application of the law touching that subject to this case. Since the contract between the parties was in writing, as before indicated, evidence as to- what was said at the time of the making thereof, or prior thereto, or as to what was intended by the parties, or any oral evidence as to the terms of the agreement, or finding in respect thereto, independently of the writing, was immaterial. That seems to have been overlooked all through the trial. The failure to appreciate it needlessly complicated what would have otherwise been a very simple case. The sole source of information as to the terms of the contract is the memorandum of December 6, 1900, indicating that appellant agreed to sell to the respondent and ship to him as ordered, at Tomahawk, Wisconsin, 400 bushels “s’k’d” potatoes, or more, at thirty-one cents per bushel, and respondent’s letter, dated October 11th thereafter, addressed to the appellant and directing it to ship 600 bushels of good potatoes.
(c) There is no finding that the potatoes were not reasonably fit for the purpose for which they were bought, nor that any particular quantity of old potatoes was destroyed be-cause the new ones were not suitable for such use.
No such finding was necessary. Counsel for appellant seem to think because the breach of contract found by the jury was that the potatoes delivered were not such as the agreement called for, that it entirely failed to make out a breach of implied warranty; that such warranty, if any existed, was that the potatoes should be reasonably fit for the purpose for which they were bought. In that counsel confuse *10tbe implied warranty, wbicli often exists, tbat an. article sold for a particular purpose knoAvn to tbe vendor at tbe time of tbe sale, is reasonably fit for sucb purpose, with tbe implied warranty tbat an article delivered in consummation of an ex-ecutory contract is of tbe kind agreed upon, as regards imperfections not discoverable at tbe time of tbe reception thereof by ordinary attention thereto on tbe part of tbe purchaser*. Tbe latter is tbe warranty which respondent was entitled to recover on in this case, if entitled to recover at all.
(d) Tbe jury should have been requested to find as á fact whether there was an implied warranty of fitness tbat tbe property delivered was reasonably, suitable for tbe use sucb property was intended for.
Here again counsel fail to appreciate tbat no sucb warranty was involved in tbe case; tbat tbe only warranty there was, if any, was against defects not permissible by tbe contract which were not discoverable by ordinary attention on tbe part of tbe purchaser, as before stated.
The sufficiency of tbe verdict is otherwise challenged as will bo hereafter shown.
Tbe next assignment of error is tbat tbe finding in tbe special verdict, tbat tbe loss of tbe good potatoes, which respondent bad when tbe new ones were received and placed tliere-witb, was tbe direct and natural consequence of tbe breach of warranty complained of, did not justify, in any event, a' recovery for sucb loss because there was no finding nor any evidence, that special circumstances existed known to tbe appellant when tbe contract was made from which it should reasonably have apprehended tbat sucb loss was liable to occur by its breach of contract. It seems to us otherwise. The evidence was undisputed tbat appellant knew respondent was a retail grocer. Therefore it must have apprehended at tbe time tbe contract was made tbat tbe placing of tbe new potatoes with old ones was within tbe probabilities. Further,' as a matter of common experience, appellant must have *11known that the mixing of potatoes that were liable to soon-decay, with good ones, would probably result in injuring the-latter. So all the essentials of the rule necessary to charge-appellant with the damages to the old potatoes to the extent that they are attributable to the breach of contract complained of, were satisfied. True, appellant was not chargeable with any damages other than such as “may reasonably' be supposed to have been in the contemplation of both parties when the contract was made as the probable result of the breach of it” (Hadley v. Baxendale, 9 Exch. 341, as condensed and approved by this court in Brown v. C., M. & St. P. R. Co. 54 Wis. 342, 11 N. W. 356, 911), and that special? circumstances enhancing the damages that would ordinarily occur must always bo brought home to the knowledge of the person charged therewith as of the time the contract was-entered into, or the sufferer will be left remediless therefor (Guetzkow Bros. Co. v. A. H. Andrews & Co. 92 Wis. 214, 66 N. W. 119) ; but that was all satisfied in this case as to the loss of the old potatoes, as we have seen.
EurtKer complaint is made that, since the evidence was undisputed and all one way that all of the seventy-five bushels-of old potatoes was destroyed by reason of the new ones being-placed thereon, the verdict that only fifty bushels were so-lost was based on mere conjecture. We are unable to see why-complaint should be made by the appellant because the jury erroneously found against it for a less loss than the whole of" the old potatoes by reason, of the contact thereof with the new ones, when the evidence was undisputed that all were so lost, if any were. Probably counsel for respondent would readily have consented to an amendment of the verdict in that respect. Hickey v. C., M. & St. P. R. Co. 64 Wis. 649, 26 N. W. 112, condemning a verdict based on conjecture, so far as we can see, has no application here. There it was clear-that the verdict was a mere prejudicial guess, while at the best, here, all that is claimed is that the jury found against. *12appellant for a loss less than that which, the -undisputed evidence established.
Did the court err in submitting to the jury this question, '“Were all; the potatoes, furnished by the plaintiff to the defendant, of the kind and quality agreed to be furnished?'"’ It is insisted that such question was fatally defective because multifarious. We shall not follow the ingenious argument of ■counsel in support of that propostion to show what appears to us to be its obvious infirmity. The difficulty therewith, In the main, grows out of want of appreciation that respondent’s claim was based wholly on breach of implied warranty that the potatoes delivered in execution of the written contract were free from latent defects rendering them not such potatoes as the contract called for. There was no need for any finding as to the terms of the contract, nor any finding as to the scope of the implied warranty. The former was in writing, the latter was a matter of law. The simple proposition submitted in the question, quoted, seems to be free from multifariousness by the most severe test that could be reasonably applied thereto.
The next assignment of error is,- in effect, that the verdict is fatally defective for want of any finding of damages on a recoverable basis, or of facts of an evidentiary character from • which the ultimate fact in that regard can be determined as a necessary conclusion. We ^ see no escape from that contention. Respondent’s general damages were limited to the difference between the market value of the property delivered at the time and place of the delivery, and the value at such time and place the same would have possessed had it been ac•cording to the contract. Aultman & T. Co. v. Hetherington, 42 Wis. 622. There was no direct evidence on that point, nor was there any finding directly thereon. The finding that the potatoes were not all according'to contract; that 200 bushels were; that 400 bushels thereof spoiled in consequence of not being such as the contract called for; that such *13potatoes as were so .called for, at tbe time and place for the-delivery thereof, were worth thirty-one cents per bushel; and that none of the potatoes were, spoiled through fault on the part of the respondent, if supported by the evidence at all points, yet failed to establish, as a matter of law, the market value of the potatoes delivered at the time and place of the delivery. There should have been a specific finding on that point. It was a vital matter in the case. Why a question in respect thereto was not submitted to the jury, while a number of questions covering mere evidentiary matters were submitted together with a number of questions which were entirely unnecessary, in view of the fact that the contract between the parties was in writing, is not easy to- understand. It might well be that 400 bushels of the potatoes delivered upon .the contract spoiled during the course of four weeks after they were put into the respondent’s cellar, and even without fault on his part, and yet that they were of some value when they were taken into his possession.
Complaint is made because the court refused to take a finding by the jury as to whether the appellant agreed that the potatoes would keep for any particular length of time. No. such question was necessary since, as before indicated, the agreement was in writing, rendering all oral statements about the potatoes, at the time it was made, entirely immaterial.
The claim is made that the finding of the jury entirely freeing respondent from all responsibility for the destruction of either the old or the new potatoes, and charging appellant with the entire responsibility in the matter, is inconsistent in view of the undisputed evidence. It looks that way. The-evidence shows that on the second or third day after the potatoes were placed in respondent’s cellar he knew that they were dangerously defective and were liable soon to become entirely worthless; that he knew from day to day, after he first discovered such condition, that it was rapidly growing worse, yet that he made no attempt to remove the potatoes from the *14■cellar, or to save tlie seventy-five bushels of old ones, but allowed all to remain as they were when be first discovered the danger, except as potatoes were picked over from time to time :to obtain a few good ones for his retail trade, till the entire lot became a decayed, filthy, and worthless mass of material. Tn the face of that, the jury exonerated respondent from all 'blame for the destruction of the potatoes, both old and new, ■and yet decided that such destruction was the natural and ■direct result of the condition the new potatoes were in when ■received by him. The fact that 400 bushels of the new pota■toes spoiled after being placed in respondent’s cellar was, as ■before indicated, only evidentiary of the value thereof when ■received. In no event could appellant be properly charged with such result unless it was one to be reasonably appre.'hended by both parties at the time of the making of the con--fcract as a circumstance probable to occur from the breach of it. If appellant is chargeable with knowledge that respondent was liable to put the new potatoes with the old ones and that the end might probably be the destruction of both, certainly respondent is chargeable with such knowledge from -the time he discovered the condition the new potatoes were in. 6 With that in mind, the finding of the jury holding the former responsible for all that occurred after the new potatoes were ■placed in the cellar and exonerating the respondent from all ■fault, even for failing to make an effort to save the old potatoes from destruction and allowing the entire lot to remain in the cellar till it became a mass of filth, seems clearly ab•surd. It is considered that the findings by the jury, in view ■ of the undisputed evidence, are inconsistent, and that the verdict exonerating respondent from all fault for the destruction ■ of any of the potatoes is contrary to the evidence. That appellant is not chargeable with any loss which respondent could by the exercise of ordinary care have prevented, is element,-ary. Fisk v. Tank, 12 Wis. 276; J. I. Casa Plow Works v. *15Niles & Scott Co. 90 Wis. 590-606, 63 N. W. 1013; Optenberg v. Skelton, 109 Wis. 241-244, 85 N. W. 356.
It is contended that tbe finding as to tbe reasonable cost of assorting potatoes in tbe cellar and' removing therefrom those which were rotten is not warranted by the evidence. Such finding was taken upon the theory that it was permissible for respondent to leave the potatoes'in the cellar for several weeks, knowing they were rapidly becoming a mass of worthless material, and pay no attention thereto, other than to sort over a few now and then to obtain small quantities of sound ones to supply retail trade, and then charge appellant with the cost of such sorting and that of removing the rotten mass that remained. That was by no means the reasonable charge for sorting potatoes and removing those that were rotten, having regard to the special damages for which appellant was liable. ’ Clearly as soon as it became apparent to respondent that the potatoes were rapidly decaying, which was in two or three days after they were received, he should have removed them from the cellar and saved the old potatoes. The reasonable cost of doing that would be the extent to which respondent could be said to have been damnified by the breach complained of. What that would have been the record is entirely silent.
Testimony was ruled out as immaterial concerning the best method of handling potatoes upon its being discovered that they are in the condition those in ’question were found to be in two or three days after respondent received them. Such evidence was certainly not immaterial. It, at least, bore directly on whether respondent exercised ordinary care to prevent any unnecessary loss accruing because of the breach complained of.
A witness, against objection, was permitted upon, a hypothesis supposed to be warranted by the evidence, to give his opinion as to whether the potatoes when, they arrived at the *16agreed place for delivery were of good, sound, white stock. It is suggested that the subject involved in the question was' not one proper to be established by opinion evidence. It seems otherwise. It may well be that the condition of potatoes, at one time may tell a far different story as to their condition a short time prior thereto, to a person of more than ordinary experience in observing such matters than to one who is not. Any subject wherein a person may become specially learned,, or skilled, is within the broad field of opinion evidence. Daly v. Milwaukee, 103 Wis. 588, 79 N. W. 752; Baxter v. C. & N. W. R. Co. 104 Wis. 307, 80 N. W. 644; 1 Wharton on Evidence, § 444. Such evidence is not confined to mere matters of professional or scientific knowledge. It extends to a very wide field, as an examination of the authorities in this-, court and elsewhere will readily show. Leopold v. Van Kirk, 29 Wis. 548; Salvo v. Duncan, 49 Wis. 151, 4 N. W. 1074; Brabbits v. C. & N. W. R. Co. 38 Wis. 289; Clason v. Milwaukee, 30 Wis. 316; Whitney v. C. & N. W. R. Co. 27 Wis. 327; Curtis v. C. & N. W. R. Co. 18 Wis. 312; Snyder v. W. U. R. Co. 25 Wis. 60; Griffin & S. Co. v. Joannes, 80 Wis. 601, 50 N. W. 785. Whether a particular matter is- or is not a proper subject for such evidence, and whether the witness presented is or is not competent to testify because of' having special knowledge in respect thereto, is not always easy to determine. • The questions in that regard, however,, relate to mere competency, and, therefore, the trial judge’s determination thereof,1 within all reasonable limits is supreme. We see no reason to overturn the judge’s ruling in the-instance before us upon the ground that the testimony was immaterial because the matter was not a proper subject for expert evidence. However, it was immaterial on another ground very clearly. The contract did not call for the kind of potatoes mentioned in the question. It merely called for good potatoes. Potatoes that were sound and reasonably good keepers, no doubt.
The court refused to permit appellant to prove what kind *17of soil tbe potatoes were grown in. That was proper. The assignment of error in respect thereto was doubtless made by reason of counsel’s overlooking the fact, often alluded to, that the written ■ contract, not the conversation in relation thereto, governed the matter. There was nothing in the writing as to what kind of soil the potatoes should be the product of.
Complaint is made because, in respect' to the interrogatory as to whether the plaintiff knew when the potatoes were sold the purpose for which they were purchased, the court instructed the jury that knowledge of plaintiffs agent in respect to the matter was imputable to the principal. The question was asked as one bearing on whether plaintiff had, at the time the contract was made, knowledge of 'special circumstances as regards how respondent would probably handle the potatoes, rendering it liable for special damages. It is conceded that as to such matter the instruction was proper. The court, however, used language to the effect that the acts, ' statements and knowledge of the agent when the contract was made were binding on the principal. It is said, that it informed the jury that plaintiff was bound by any warranty the agent may have made, though he was not specially authorized thereto by his principal. That may be, but there was-no such warranty involved in the question, and it is not likely the jury understood the instruction to be broader than the-subject to which it related, though it would be safer to use-more guarded language.
The court instructed the jury on the question as to whether it was agreed that the potatoes should be examined when they . arrived at Tomahawk and accepted or rejected before being taken from the car:
“You are to bring your own knowledge and experience in determining what the evidence and all the evidence and circumstances submitted for your consideration applicable to this question really establishes and means.” •
*18The question, itself was out of place. The written contract made no mention of any such agreement, moreover the instruction, so far as it permitted the jury to apply to the matter any special knowledge of their own, was erroneous. That is according to elementary principles.
On the question as to whether a person of ordinary intelligence in the exercise of ordinary care, by inspecting the potatoes after they arrived at Tomahawk and before removing them from the car, could have determined whether they were the kind and quality agreed upon, the court instructed the jury in these words: “lie would not be required to look at the whole mass in the car or look at them other than in a fair and reasonable way,” etc. The complaint that the province of the jury was thereby invaded seems to be warranted. The nature of the inspection necessary to come up to the standard of ordinary care in the circumstances presented was wholly a subject for the jury to determine. Whether an examination sufficient to enable one to inform himself in a general way of the character of the entire car of potatoes may or may not have been required to come up to the necessary standard of care, was a jury question. There are but few situations where it is safe to instruct, as a matter of law, what is and what is not consistent with ordinary care.
Now we have specially or generally considered all of the assignments of error. Those that have not been named specifically are involved in and decided with those which are. The judgment must be reversed and the cause remanded for a new trial. It is hoped that when such trial shall occur only the case made by the pleadings in view of the undisputed fact, that the potatoes were purchased under a written contract, will be tried and submitted to the jury; that all extraneous matters will be excluded. The contract must be held to determine the question as to the kind of potatoes which were bought. They were simply good potatoes. That doubtless called for potatoes of good merchantable quality, *19and tbat called for at least ordinary keeping qualities. When it comes to a question of damages it should not be forgotten, as to general damages, that the true standard for breach of implied warranty, as in a case of this kind, is the difference between the market value of the property delivered at the time and place it was received and the market value at such time and place of property of the kind the contract called for. In addition such special damages as are properly claimed in the pleading, established by the evidence, and allowable by correct legal principles as herein outlined, may be recovered. Further, it must be borne in mind upon a second trial that it was not consistent with ordinary care for respondent to allow the potatoes to remain in the cellar 'in contact with good stock, with knowledge of all the facts, till all the potatoes became a mass of filthy worthless material.
By the Gourt. — -The judgment is reversed, and the cause remanded for a new trial.