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PROBL. II. How to Measure Boards, Glass, Pavement, Wainscot, and the like.
IN the last Problem we have shewed that Boards, Glass, Pavement and Wainscot, and the like, they are commonly accounted by the Foot or Yards; Therefore to make this plain, we shall instance only upon Boards which are cut out in long squares commonly.
Take the length and breadth in Inches and Parts, Multiply one by the other, the Product will shew the Content in Inches; (that divide by 144 the Numbers of Inches in one Foot, the Quotient will tell you the Number of Feet, and the remainder is Inches.
* 1.1Admit I have a Board that is 7 Foot long, and 18 Inches broad; Multiply 84 Inch. which is in 7 Feet by 18 Inches, the Product is 1512; which divide by 144 the Num∣ber of Inches in a Foot of flat-measure, and the Quotient shews 10 feet, and 72 remains, which is ¼ 144; therefore the Board contains 10 foot ½; but many times the Board falls out to be broader at one end, then it is at the other, add together the breadth at each end; then take the ½ for the true breadth.
And Work as before; But commonly Artificers have a Useful Line put upon their Rules for their ready Measuring of Board and Timber-measure; but this is the Exactest way, though that is near; and what have been said of Board-measure, only the same is to be understood is the way of Measuring not only Boards and Glass; but likewise all manner of Wainscot, Pavement, Floors, and such like; they depend upon one and the same Geometrical Ground, though they be reckoned by different measures, as you see by the Perch, Rod, Square, Yard or foot according to the Custom of the Place, there∣fore needs no further Example.
Extend the Compasses always from 12 Inches unto the breadth 18 Inches, the same extent will reach from the length 7 foot, unto the Number of Square foot in the Board, which is 10 5/10 foot.
AB 18 Inch × AD 7 foot/ = 10 4/10 feet.