The facts are simply stated. At approximately 6:30 P.M. on the evening of March 10, 1970, the plaintiff was operating her 1964 Ford convertible in an easterly direction on a two-lane macadam highway known as New York State Route 31 toward her son's home located on an intersecting road. The weather was cool, clear and dry; and the visibility, though it was near dusk, was good. Route 31 is a 24-foot-wide divided highway with a speed limit of 50 miles per hour. Plaintiff testified that when she neared the intersection, she reduced the speed of her automobile from 40 to 20 miles per hour and simultaneously turned on her left directional indicator; and as she was doing this, plaintiff looked in her rear view mirror and saw a set of headlights "way back"; she then neared the center line of Route 31, and, while she was turning left to enter Camp Road, was struck in the westbound lane of Route 31 by the defendants' tractor-trailer which was in the process of attempting to pass her automobile. The right front fender of the tractor-trailer came into contact with the left front portion of the plaintiff's automobile, and, as a result of the initial impact, the plaintiff was ejected from her vehicle, which then rolled over her in such a way that her legs were pinned under the left rear wheel. Although the plaintiff's automobile was equipped with seat belts, she was not using the device at the time of the accident.