Chapter 4: WALLPAPER PATTERNS



This chapter is devoted to a fairly detailed description, in strictly geometrical terms always, of the seventeen planar crystallographic groups (wallpaper patterns). No attempt to prove that there exist precisely seventeen types is made in this chapter, but the Crystallographic Restriction is proven in full detail in section 4.0 (which may just be browsed through at first reading). Emphasis is placed on how wallpaper patterns may be derived from each other or from border patterns.