Opinion by

This action was brought to recover the sum of $825 for professional services rendered by the plaintiff to Dr. Win. H. Mat-lack, who was afflicted with partial paralysis in October, 1893, and continued in precarious health until July, 1896, when his illness resulted in death. During this interval Dr. Matlack received counsel and service, from a number of his professional brethren, one of whom, the plaintiff, claims from his estate the amount mentioned, on the basis of one dollar for each visit made by him. Dr. Matlack and the plaintiff advocated and practised the same system of medicine in the borough' of Downingtown, and were professional friends.

On the trial of the cause the defendant offered evidence to prove that it was the universal custom with physicians not to charge for their attendance upon their fellow physicians; that the ethics of the profession prohibited such charges being made; that it was the custom among physicians in Downing-town not to charge for attendance on physicians, one physician on another; that as a matter of professional ethics it was regarded as improper and unprofessional for one physician to charge another for his attendance. Evidence to sustain each of these offers was rejected for the reason stated in excluding the evidence under the first offer, viz: “I do not think that the evidence is admissible. The law presumes where one renders services to another that the party who receives them contemplates to pay for them. There is an implied contract. This is an effort to deprive one of that legal presumption by showing that it is a custom amongst physicians in the neighborhood not to charge each other, and whilst that may be true among the bulk of the physicians I do not think it can control the intention of one man, or override the presumption that the law creates in his favor, that where he renders a service to another, whether a physician or not, there is a contract on the part of the party receiving it to pay for it.” The rejection of the evidence as offered warrants us in assuming that the custom could *12be proved as it was alleged in the offers: Helme v. Ins. Co;, 61 Pa. 107. The language used by the court assumed that, to establish the custom, the offers would be supported by sufficient proof, and that the plaintiff' knew of it, but, notwithstanding tiffs, it was not admissible, by proof of such a custom, to override the presumption that the law creates in favor of one rendering service to be paid for it, and that by Dr. Matlack accepting the services of the plaintiff an implied promise to pay in money was created. But, to sustain an implied promise to pay there must be circumstances, which, according to the ordinary course of dealing and common understanding of men, show a mutual intention to contract in that manner: Hertzog v. Hertzog, 29 Pa. 465; Walker v. Marion, 148 Pa. 1. What were the understanding and intention of these parties ? Under all the circumstances of this case, this was a question for the jury. It was submitted to the jury by the learned judge, it is true, but without all the evidence, which, if fully coming up to the offers, would have a legitimate tendency to rebut the implication of a promise to give pecuniary compensation for the services rendered. It is unquestionably the law, that before a mere usage of trade, or a custom, can be so firmly imbedded in the law as to govern the rights of parties, it must be so certain, uniform and notorious, as probably to be known to and understood by the parties entering into the contract: Ambler v. Phillips, 132 Pa. 167; Weld v. Barker, 153 Pa. 465. In the case in hand, the offers, as interpreted by the court below, not only assumed that the custom could exist; be known by the parties; was a reasonable one, yet it would not be evidence upon the question whether in the intention and understanding of the parties, the services rendered by- the plaintiff were gratuitous. The defendant urged that the excluded evidence was not offered to nullify or defeat a contract of employment and compensation therefor, but tended to prove the manner of payment, by a known, certain, reasonable and universally recognized custom; that instead of receiving in money the compensation usually given for like service, the attending physician, accepted in full payment therefor, the benefits and advantages of a professional comity, which assured to him valuable professional advice and skill under similar conditions; the continuing good opinion of the members of a learned profession which was *13deemed essential to success in his calling; and confidential scientific counsel in matters pertaining to his health and reputation. If the excluded evidence would show that the service rendered by the plaintiff was in pursuance of such an understanding between the parties, it would be proper for the jury to consider it along with the other evidence in the case. The question is not whether the custom would, of itself, be a complete defense to the action, but whether it was competent evidence in connection with the other significant circumstances bearing upon the issue of fact submitted to the jury. For this purpose, at least, the evidence embraced in the first offer should have been admitted. The code of ethics ofthe profession would not be evidence without accompanying proof that the plaintiff and Dr. Matlack mutually acknowledged themselves as bound by it at the time the services were rendered. The first and fifth assignments of error are sustained; the judgment is reversed and a venire facias de novo awarded.