Then try drawing four equal quad- ^ rants. Note: the ends are always x rounded, never pointed.
You might find it helpful to sketch a rectangle around the tick marks. This creates four more guide lines within which the shapes can be judged and compared (above).
Another good technique is to draw the curve carefully in one quadrant. Then transfer (tracing paper works well) this shape to the other three quadrants, using the axes as reference lines (above).
~ A true circle can always be sur-s/ rounded by a true square. The center /V of the square (found by drawing two
\ diagonals) is also the center of the \ circle (left).
\ The circle in perspective (right)
l(2) shortened square. Drawing the diag-/ onals will therefore give the center / of both square and circle. We know / from page 68 that this point is not midway between top and bottom lines. So the circle's diameter drawn through this center point is also not midway between top and bottom.
Yet we know (right) that the major axis of an ellipse must be mid-\ way between top and bottom lines.
\ So, combining the two drawings
\ (right) we see that the circle's diam-\ eter falls slightly behind the ellipse's 1/ major axis. (Note, too, that the 1 minor axis is always identical with // the most foreshortened diameter of / / the circle.) yi/ The top view (left) explains this seeming paradox. The widest part of / the circle (seen or projected onto the picture plane) is not a diameter but PiANS simply a chord (shown dotted). It is this chord which becomes the major axis of the ellipse, while the circle's true diameter, lying beyond, appears and "projects" smaller.
¡4- AXld major axis
Note: points of tangency between ellipse and square (1,2,3,4) are exactly at diameter lines, just as in the true top view (upper left).
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