Franklin magic square

One day in 1771, Benjamin Franklin, tired of hearing political debates, amused himself by creating the following magic square, now called a Franklin magic square:

The magic constant is 260. Furthermore, half any row or column (positions 1 to 4 or 5 to 8) equals half the magic constant. Two centuries later, Joseph Madachy realized that some half diagonals from the corner to the center also give 260.

Some other 8 by 8 magic squares with these properties are also called Franklin magic squares.