Lay out this plate in the same manner as the preceding plates.
Locate the three points A, B, and C with a distance between A and B of about 2 inches and a distance between A and C of about 2 1/4 inches. Connect A and B and A and C. Erect perpendiculars to the middle points of A B and A C as explained in Problem 1. Now draw light pencil lines connecting the intersections I and J and E and F. These lines will intersect at 0.
With 0 as a center and a radius equal to the distance 0 A, describe the circumference passing through A, B, and C.
The point 0 is equally distant from A, B, and C, since it lies in the perpendiculars to the middle points of A B and A C. Hence the circumference will pass through A, B, and C.