If a figure shown in a book or in any picture is to be enlarged the following method is very simple:

Enclose the figure in a rectangle and divide it in quarter inch squares, like the drawing of the duck in Plate 16.

If the drawing is to be enlarged twice the original size, draw a rectangle on a piece of paper or cardboard twice as large as the picture. Divide it into exactly the same number of squares, which will now be twice as large as before, or one-half inch on a side. Letter and number all parts to agree.

Start now and sketch the enlarged figure, having the lines pass through the same places in the squares of the large rectangle as in the small.

With a little patience it will be surprising how accurate a copy can be made.

A picture may be reduced by the same method.