Thus, in charging the doctrine of comparative negligence, the trial court must instruct the jury that the negligence of the plaintiff, in order to bar his recovery, must have proximately contributed as a cause of the injury received by the plaintiff. Jackson v. Matlock, 87 Ga. App. 593, 595 (4) ( 74 S.E.2d 667); Harmon v. Southwell, 98 Ga. App. 261 ( 105 S.E.2d 596); Western A. R. v. Dalton, 101 Ga. App. 468 ( 114 S.E.2d 293). The failure by the trial court to charge on proximate cause requires a reversal. Judgment reversed. Bell, C. J., and Shulman, J., concur.