Complex sentence: The first executive toy may have been a gadget designed by the great mathematician and engineer Philo of Byzantium (about 280 BC-about 220 BC), an octagon-shaped ink pot with openings on each side.
Split into simpler sentences: The first executive toy was probably a gadget designed by the great mathematician and engineer Philo of Byzantium (about 280 BC-about 220 BC). It was an octagon-shaped ink pot with openings on each side.