I found an old pill that is round on the sides flat on the bottom and has a thin hexagon raised on the top. It is yellow but may have changed color over time. I believe it was from the 1970's. It has a score mark halfway horizontally across the hexagon. (to break it in half?) above the score line is the logo CL where the L is dropped and centered on the C like a symbol for centerline. and below the scoreline is the number 110.