KEY TOWNSHIPS extent of commutation (symbol surrounding township) N.B. — In mixed townships, where different rates of commutation for free and bond units are specified, the symbol for the free unit is represented by a continuous line and that for the bond unit by a broken line, e.g. Bodysgaven IN THE TWELFTH AND THIRTEENTH CENTURIES ● free 0 bond ⊙ mixed rer cent □ 0-15 A 16-30 0 31-45 0 46-60