Place paper so that the long edges will be parallel with the front edge of desk. Bisect the front edge of paper.: three inches from this point and directly towards the back edge of paper place a point; with this point as a center, draw a six inch horizontal line; using this line as a base, construct a six inch equiangular tnangle by means of arcs; bisect all sides of this triangle, join points of bisection in right side with point in left side; connect both of these points with center of base.

Open the dividers equal to the length of side of small triangle; place the metal point at lower right corner of upper triangle; with this point as a center construct a circular margin on left side of upper triangle; construct similar margins on the base of lower left triangle, and on the right side of lower right triangle.

Transfer drawing on card-board to a scale of three to four; cut, crease, fold and glue.