Cords sharing a beam: equal and proportional loads
Symmetric supports load equally; an off-center cord loads in inverse proportion to its distance
Folio 168r states two principles for a beam suspended by two cords, illustrated by faint tick-marked beam diagrams. First, cords that hold the beam between them by its extremes are equally loaded. Second, when one cord is drawn nearer the center of the weight, its load stands to the other's in the same ratio as the smaller to the greater of the two spaces between the beam's middle and the cords. Numbers such as 5 1/3, 2 2/3 and 8/3, 16/3 label the divided spans.
On this page
Symmetric supports carry equal load
Those cords that support the suspended beam between them by its extremes are equally loaded by it. The tick-marked beams show weights hung over evenly divided spans.
Load in inverse proportion to distance from center
When one cord is brought nearer the center of the weight, its load stands to the other's as the smaller stands to the greater of the two spaces that lie between the middle of the beam and the two cords.