The xylon, in which naubia are measured. The royal (xylon) 9 comprises 3 cubits, 18 palms, 72 fingers; 10 the private (xylon) comprises 2⅔ cubits, 16 palms, 64 fingers, so that the surveyor's schoinion comprises 32 royal xyla, and 36 private (xyla).
Source: wiktionary