Newman, J.
The record contains no certificate of the trial judge that the bill of exceptions contains all the tesr *637timony given, upon the trial. In the absence of such certificate, the presumption is that every fact within the issue and essential to support the judgment was proved upon the trial. Lee v. Campbell, 77 Wis. 340. So there can be no review of the case upon the testimony here, nor any inference inconsistent with the verdict drawn. Morrow v. Lander, 77 Wis. 77. Sufficient of the testimony is preserved in the bill of -exceptions to show that there was testimony tending to prove all the facts essential to support the plaintiff’s judgment.
But the defendant sees a fatal error in this instruction, which the court gave to the jury: “ The testimony shows that this boy [the plaintiff] was eighteen years old,— nearly nineteen. It is claimed on the part of the plaintiff that he was a boy of tender years and therefore the same degree of care and discretion is not to be expected of him as would be of an adult or grown-up person. It is claimed on the part of the defendant, on the other hand, that although he was a minor he had arrived at such an age of discretion that he had, practically, the same discretion, and should be 'held to the same rule of care and prudence, as if he were an .adult or person of mature age. How this is a question which belongs entirely to you to determine. You have seen him on the witness stand and heard him testify. You must judge of his intelligence and capacity, and how much, if any, allowance should be made for his youth.”
This is construed by defendant’s counsel to be, in effect, an instruction to the jury that they might consider the appearance of the plaintiff, as he had been exhibited before them on the witness stand, in determining the question of his intelligence and capacity to apprehend and avoid the dangers incident to his employment. It seems to be capable of that interpretation. The jury may have so understood it. With that interpretation, defendant’s counsel considers it plain error. But Hermann v. State, 73 Wis. 248, seems to *638be a strong case in point to sustain the instruction. And' that was a criminal case, where, if anywhere, full proof is. required. The questions were as to a young woman’s age,, and the impression, in that respect, which her appearance should have made upon the defendant. It was held competent for the jury to give weight to their own observation of the young woman in court, during the trial, in the determination of these questions. No case in conflict with this view has been found. The question to be decided in the instant case was not an expert question to be decided upon the testimony of expert witnesses. It was a matter of common knowledge and observation. It was not susceptible of-proof by opinion evidence. The jurors, having had observation of the plaintiff, were as competent to form an opinion of his intelligence and capacity, as related to the matter under investigation, as other witnesses would be. Much that is said by way of argument in Washburn v. M. & L. W. R. Co. 59 Wis. 364, seems to support this view. But the question involved in that case was an expert question to be decided upon the testimony of witnesses having peculiar knowledge of the matter involved. This was the value of lands condemned for railway purposes. The court held that,, while for many purposes it was competent for the jury to-act upon the knowledge which they had obtained from a view of the premises, yet on this question of the value of the-lands they were bound by the testimony of the witnesses-who had peculiar knowledge and were experts upon the-question. It does not seem, in any way, to conflict with Hermann v. State or the cases which support it. The instruction was not error.
Several alleged errors set out in the brief of counsel for-the defendant, but not urged upon the argument, are found to be unimportant and are not considered at length.
' By the Oourt.— The judgment of the circuit court is affirmed.