The Second FIGURE.
The Manner of delinating a Square in Perspective.
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EFORE the Suqare A. which is ſuppos'd to be drawn on separate Paper, can be laid down in Perſpective, two parallel lines muſt 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 Diſtance E. Then, when the Length and Breadth, and DC be equal to the Length, let the viſual Lines BO, CO be drawn from the points B and C to the Point D to the Point of Diſtance. Laſtly, where the LIne DE cuts the visual CO, make GF parallel to CB: and you have the Square Opitcally contracted, or fore-ſhorten'd in prerſpective.
To ſpare Time and Pains, eſpecially 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.
