1. The Sands of Time and the Salt of the Earth
  Thinking Deeply About the Geometry of Piles of Sand and Pillars of Salt.
Troy Jones
Waterford School
PCMI 2006

2. Dreams of Adventure Undaunted Courage Shackleton’s Nimrod Expedition
“The real voyage of discovery lies not in finding new lands, but in seeing with new eyes.”
Marcel Proust, French novelist/philosopher

3. Inspiration for seeing with new eyes.
Romulo Lins
Mathematics Professor
State University of Rio Claro, Brazil
PCMI Participant 2002

4. Example from Algebra 2 textbook

5. Larson, Boswell, Kanold, and Stiff /Algebra 2/: McDougal Littell, 2004
Larson, Boswell, Kanold, and Stiff /Algebra 2/: McDougal Littell, pp. 487.

6. Larson, Boswell, Kanold, and Stiff /Algebra 2/: McDougal Littell, 2004
Larson, Boswell, Kanold, and Stiff /Algebra 2/: McDougal Littell, pp. 489.

7. What’s Happening?

8. Model salt cone with Cabri 3D

9. Model salt ridges with Geometer’s Sketchpad

10. Model of elliptical salt ridge with Cabri 3D
Click on the figure to animate
Drag A to change the height of the cylinders
Drag B, C, and D to change the radii of the cylinders
Right click and drag to change the viewing angle