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

William Leybourn London : Printed for Hannah Savvbridge ..., 1684

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