 One of the early Western students of Islamic patterns , Ernest Hanbury Hankin , defined a " geometrical arabesque " as a pattern formed " with the help of construction lines consisting of polygons in contact . " He observed that many different combinations of polygons can be used as long as the residual spaces between the polygons are reasonably symmetrical . For example , a grid of octagons in contact has squares ( of the same side as the octagons ) as the residual spaces . Every octagon is the basis for an 8 @-@ point star , as seen at Akbar 's tomb , Sikandra ( 1605 – 1613 ) . Hankin considered the " skill of the Arabian artists in discovering suitable combinations of polygons .. almost astounding . " He further records that if a star occurs in a corner , exactly one quarter of it should be shown ; if along an edge , exactly one half of it . 
