This section is from the book "Paper Folding And Cutting", by Katherine M. Ball. Also available from Amazon: Paper folding and cutting.
TO make, by folding and cutting, an equilateral triangle, a hexagon, a three-pointed star, a six-pointed star, a trefoil, a hexafoil, a three-leaved rosette, and a six-leaved rosette, from a square, a circle, or any regular or irregular plane figure.

Fig. \


FIg-3


Fig. 5
Beginning with the square, Fig. 1, fold I on 2, folding from o, and crease with the thumb-nail, thus obtaining Fig. 2.
To obtain Fig. 3, trisect the 180°fold in Fig. 2, and fold the right part on the adjoining one, folding from o. For Fig. 4, fold the remaining part, seen in Fig. 3, on top of the first fold, and crease. For Fig. 5, bisect and fold Fig. 4.

Fold to Fig. 4, and cut from 1 to 2. The line 1-2 must be at right angles to 3-0-.

Fold to Fig. 4, and cut from 1 to 2. Points 1 and 2 must be equally distant from o.

Fold to Fig. 4, and cut from 1 to 2. Point 2 is obtained by quadrisecting 3-0.
Fold to Fig. 5, and cut from 1 to 2. Point 2 is obtained by trisecting 3-0.

Fold to Fig. 4, and cut from 1 to 2. Point 2 is the intersection of the line 3-0 and the arc. The arc should be a semicircle, having its centre on the line 1-0.

Fold to Fig. 4, and cut from 1 to 2. The arc 4-1 should be a quadrant, with 3 as centre. The line 2-4-1 must be at right angles with 5-0.


Fold to Fig. 5, and cut from 1 to 2. Point 2 is the tangential union of the arc and the line 3-0. The arc should be a semicircle, having its centre on the line 1-0.

Fold to Fig. 5, and cut from 1 to 2. The line 2-4 must be at right angles to 1-0, and the arc 3-1 should be a quadrant with 4 as centre.
Fold to Fig. 3, and cut from 1 to 2.





FiG I

Tig 2



For the triangle, fold to Fig. 3, and cut from 1 to 2. For the hexagon, fold to Fig. 4, and cut from 1 to 2. For the six-pointed star, fold to Fig 5, and cut from 1 to 2. Point 2 is obtained by trisecting 3-0.

Fold to Fig. 5, and cut from 1 to 2.




 
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