But they are definitely placed like 4 corners of a square ... look at the two diagonals at the bottom. They seem to be intersecting each other at perpendicular angles. Since the table is circular at the top, the 4 legs at the bottom have to be the corners of a square.

It could even be setup as the corners of a rectangular if the top was elliptical ... it wouldn't matter too much for the purposes of stability.

Ss