Placing four weights on the experimental balance
Rule for pairing the greatest, least and two middle weights as counterweights
A horizontal beam drawn at the top carries four hanging weights along a given line a b n c d, marked with the values 3 2 5 1. The rules that follow explain how to balance them: of the four weights the two middle ones serve as counterweights to the greatest and the least, and the heaviest hangs nearest the pole. One middle weight is chosen to counter the greatest, and the arms of the balance are then divided using the remainders left after subtracting weights from one another, yielding the true spacing for each load.
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Pairing four weights on the beam (a b n c d; 3 2 5 1)
Of the four given weights, the two middle ones are placed opposite as counterweights to the greatest and the least gravity, and the greatest always hangs nearer the pole of the balance than the least. Either middle weight may be chosen to counter the greatest; the one so chosen hangs nearer to it.
Dividing the arms by the weight remainders
Take the chosen middle weight from the greatest, and from their remainder divide each arm of the experimental balance to obtain its true divisions. Then subtract the two middle weights from the greatest and least, and use their remainder to set the space between the greatest and least weight, and likewise between the two middle ones.