Weights on a pair of connected suspended beams
A continuous beam shares its load like discrete weights, proved by proportion (n m : a n)
Two beams linked together hang from cords, marked with the values 8/5 and 32/5 and the letters a, n, m. Leonardo argues that the continuous mass of a beam distributes weight to its cords exactly as separate discrete weights would, for any number of cords and loads. The load each cord bears stands in the same proportion as the opposite spaces between the cords and the beam's centre: since space n m is one quarter of a n, the load 8/5 is one quarter of 32/5.
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A continuous beam behaves like discrete weights
Leonardo concludes that the continuous quantity of the beams gives weight to the cords of the same nature as discrete weights would, in every case and for any number of cords and loads. Each cord passes to the balance exactly as much weight as it supports.
Load in inverse proportion to opposite spaces (8/5 : 32/5)
The supported parts always stand in the same proportion as the opposite spaces enclosed between the cords and the centre of the beam. Since space n m is a sub-quadruple (one quarter) of a n, so oppositely 8/5 at a is one quarter of 32/5 at n.