Core the tomatoes, and thinly slice off the ends. Cut the tomatoes into half- inch-thick slices (you'll get about 3 or 4 slices per tomato) and set aside.
Combine the cornmeal and salt on a dinner plate. Mix until uniformly blended.
Dredge the tomato slices in the cornmeal mixture, pressing it into the cut surfaces of the tomatoes to create a thick coating.
Fry the tomatoes on each side for 8 to 10 minutes, or until crisp and golden. You might need to add a little more butter at some point to keep them from sticking.