Poncelet Transverse
Let a Circle 
lie inside another Circle 
. From any point on , draw a tangent to and extend it to . From the point, draw another tangent, etc. For 
tangents, the result is called an -sided Poncelet Transform.
References
Dörrie, H. 100 Great Problems of Elementary Mathematics: Their History and Solutions. New York: Dover, p. 192, 1965.
- Spherical Point System
- Spherical Polygon
- Spherical Ring
- Spherical Sector
- Spherical Segment
- Spherical Shell
- Spherical Spiral
- Spherical Symmetry
- Spherical Tessellation
- Spherical Triangle
- Spherical Trigonometry
- Spherical Vector Harmonic
- Spheroid
- Spheroidal Harmonic
- Spheroidal Wavefunction
- Sphinx
- Spider and Fly Problem
- Spider Lines
- Spiegeldrieck
- Spieker Center
- Spieker Circle
- Spigot Algorithm
- Spijker's Lemma
- Spindle Cyclide
- Spindle Torus