Even when cars were new back in the 1940’s and 1950’s the vacuum wipers always needed a little help. Because many people smoked during those days, pouch tobacco (like the Bull Durham Brand) was common. During those days it was common practice to rub the tobacco pouch across the outside of the windshield. The "juice" in the tobacco acted as a lubricant that made the job the vacuum powered windshield motor had to do a little easier. The "juice" also made it easier to get the bugs off of the windshield. This is the job that products like "Rain-X" do today.