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The line of proportion or numbers, commonly called Gunter's line made easie: : by the which may be measured all manner of superficies and solids; as boards glass, pavement, timber, stone, &c. Also, how to perform the same by a line of equal parts, drawn from the centre of a two-foot rule. Whereunto is added the use of the line of proportion improved: whereby all manner of superficies and solids may both exactly and speedily be measured, without the help of pen or compasses, by inspection, looking only upon the ruler
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