Some castle defenses

Usage examples of moats.

Wang Lung was furious and he beat the locusts and trampled on them and his men flailed them with flails and the locusts fell into the fires that were kindled and they floated dead upon the waters of the moats that were dug.

Then Wang Lung called his own laborers and Ching stood silent and ready beside him and there were others of the younger farmers, and with their own hands these set fire to certain fields and they burned the good wheat that stood almost ripe for cutting and they dug wide moats and ran water into them from the wells, and they worked without sleeping.