PRACTICAL 3: STEREOGRAPHIC PROJECTION AND THE STEREONET.
	Another way to define small circles: Let's take a set of planes striking N000. We draw on each plane a set of lines passing through the center of the equatorial plane (i.e. the center of the sphere), the pitch of each lines increasing by 10º. The stereographic projection of those lines lies on the great circles of the plane carrying them...				...we can also note that the stereographic projection of lines with same pitch defines another alignment along small circles.