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 The Second FIGURE.

The Manner of delinating a Square in Perspective.

EFORE the Suqare A. which is uppos'd to be drawn on separate Paper, can be laid down in Perpective, two parallel lines mut be drawn; one of the Plan, the other of the Horizon, as is already intimated; noting in the Horizontal Linte the Point of Sight O, and the point of Ditance E. Then, when the Length and Breadth, and DC be equal to the Length, let the viual Lines BO, CO be drawn from the points B and C to the Point D to the Point of Ditance. Latly, where the LIne DE cuts the visual CO, make GF parallel to CB: and you have the Square Opitcally contracted, or fore-horten'd in prerpective.

To pare Time and Pains, epecially in Figures that abound in Lines, fold your Paper in the middle, and make use of it to trnasfer the Breadth and Length of the Square, into the Line of the Plan.