I received the photo below from a friend, but I'm not sure where he got it. It's not dated, but someone has suggested the 1940s. Could be, but I that's exactly the way I remember the ferry in the 1950s.
The ferry is the Cone Johnson, and we see it as it docks at Bolivar. This Wikipedia article says the three original ferries were the Cone Johnson, the R. S. Sterling, and the E. H. Thornton, each a namesake of a Director of the Texas Department of Transportation. (Of course, Sterling was also a governor.)
Another article I've read said the State charged $.25 a car to travel on the ferry until 1949, when it became free of charge.