A finding as a matter of law that a party is negligent should be made only when reasonable men could reach but one conclusion from the evidence. Canupp v. Wade, 205 Va. 850, 854, 140 S.E.2d 659, 662 (1965). The evidence of defendant Biggs is not incredible nor could reasonably fair-minded men only conclude from it that he was guilty of negligence which was a proximate cause of the accident.

In order to recover for the damage to his automobile the plaintiff must prove negligence on the part of the defendant. Cf. Canupp v. Wade, 205 Va. 850, 140 S.E.2d 659. Plaintiff accordingly charged in his motion for judgment that the defendant negligently caused his damage. In Driver v. Brooks, 176 Va. 317, 327, 10 S.E.2d 887, 892, we cited the case of Cohen v. Petty, 62 App. D.C. 187, 65 F.2d 820, as authority for the principle that "where the driver of an automobile is suddenly stricken by an illness, which he has no reason to anticipate and which renders it impossible for him to control the car, he is not chargeable with negligence.

So far as his testimony is concerned, what occurred on the highway during that interval must be left to speculation and conjecture, which are not sufficient to contradict anyone. The cases of Newman v. Dalton, 206 Va. 119, 141 S.E.2d 677 and Canupp v. Wade, 205 Va. 850, 140 S.E.2d 659, relied upon by the plaintiff, are clearly distinguishable from the case before us and are not, therefore, controlling. In the Newman case, the plaintiff was proceeding north on a secondary road approaching a primary highway.

We have repeatedly said that the jury is the proper tribunal to decide the question of negligence if reasonable men may differ as to the conclusion to be drawn from the evidence, or if the conclusion is dependent upon the weight to be given the testimony. Canupp v. Wade, 205 Va. 850, 855, 140 S.E.2d 659, 662 (1965); Adams v. Allen, 202 Va. 941, 946, 121 S.E.2d 364, 368 (1961); 13 Mich. Jur., Negligence, Sec. 64, p. 595. Resolving conflicts in the evidence is a traditional prerogative of the jury, and a determination as a matter of law that a party is guilty of, or is free from, negligence should be made only where the evidence is such that reasonable men, after weighing the evidence and drawing all just inferences therefrom, could reach but one conclusion.

* *" Weddle, Administratrix v. Draper, 204 Va. 319, 322, 130 S.E.2d 462, 465, and cases cited. See also Canupp v. Wade, 205 Va. 850, 854, 140 S.E.2d 659, 662. The evidence in the present case was much the same as that in Joffre v. Canada Dry Ginger Ale, Inc., 222 Md. 1, 158 A.2d 631. The plaintiff there was injured by a fragment of glass from a soda bottle which shattered in the store and she sued the bottler and the store.

' " See also Adams v. Allen, 202 Va. 941, 945, 121 S.E.2d 364; Spiegelman v. Birch, Adm'r, supra; Carner, Adm'r v. Hendrix, supra; and Canupp v. Wade, 205 Va. 850, 854, 140 S.E.2d 659. We do not find that the admission of the testimony was prejudicial.

If her admission be accepted, the cause of the accident is left to conjecture, and a finding of gross negligence cannot be based upon conjecture. Barnes v. Barnes, Adm'r, supra (footnote 1); see Canupp v. Wade, 205 Va. 850, 140 S.E.2d 659 (1965), and Weddle, Adm'x. v. Draper, 204 Va. 319, 130 S.E.2d 462 (1963), dealing with ordinary negligence. Under the other version, the jury could have based its finding of gross negligence only upon the plaintiff's conclusion that Burke was driving "too fast".