Also, because the beams would sag (albeit only slightly) over time, every two years during renovations the beams would be turned over to resist the force of gravity, thus keeping them as good as new.
雖然下垂的幅度很小，但人們就會用兩年一次整修的機會，將橫樑翻轉過來以抗地心引力，如此即可周而復始地利用。