Proportional rules for the weights on two cords
How changed and remaining loads relate to the rod's spaces
This all-text page gathers the proportional laws of Leonardo's suspended-rod problem into a compact set of rules. The change of weight a cord gains through its motion relates to its former weight as its motion relates to the rest of the rod; the changed weights on the two cords relate as the spaces between the cords and the rod's centre; and the weights that remain relate oppositely to those same spaces. A closing statement repeats that the weight shifting between the cords is proportional to the cord's motion against the remainder of the rod.
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Change of weight proportional to the cord's motion
The variation of weight a cord acquires through its motion has the same proportion to its former weight as its motion has to the remainder of the rod. The changed weights on the two cords relate as the spaces interposed between the cords and the rod's centre, while the remaining weights relate oppositely to those spaces.
Weight moving between the cords
The weight that moves between the cords stands in the same proportion to the original weights as the motion made by the cord bears to the remainder of the rod. This restates the load-transfer rule that governs the whole sequence of leaves on the suspended rod.