If they intersect one another, as in the figure, and they are below the eye, part of the bottom of the dish is seen within it.
Fig. 66.
To avoid confusion, let us take then two intersecting circles without the inclosing squares, as in [Fig. 66.]
Draw right lines,
a b
,
c d
, touching both circles externally. Then the parts of these lines which connect the circles are the sides of the dish. They are drawn in [Fig. 65.] without any prolongations, but the best way to construct them is as in [Fig. 66.]
If the circles do not intersect each other, the smaller must either be within the larger or not within it.