diff --git a/tornado/doc/geom.fig b/tornado/doc/geom.fig
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+#FIG 3.2  Produced by xfig version 3.2.5b
+Landscape
+Center
+Metric
+A4      
+100.00
+Single
+-2
+1200 2
+6 675 6795 4095 8370
+4 0 0 40 -1 18 12 0.0000 4 195 1845 675 6975 Fz: centripetal force\001
+4 0 0 40 -1 18 12 0.0000 4 195 1815 675 7200 Fz = m*r*4*pi^2*f^2\001
+4 0 0 40 -1 18 12 0.0000 4 195 2040 675 7650 Fg: gravitational force\001
+4 0 0 40 -1 18 12 0.0000 4 195 2715 675 7875 Fg = m*cos(theta)*9.81 m/s^2\001
+4 0 0 40 -1 18 12 0.0000 4 195 3390 675 8325 theta: inclination of plane of rotation\001
+-6
+1 3 0 2 0 7 50 -1 -1 0.000 1 0.0000 6300 4500 45 45 6300 4500 6345 4500
+1 3 0 2 0 7 50 -1 -1 0.000 1 0.0000 6300 4500 3600 3600 6300 4500 9900 4500
+1 3 0 2 0 7 50 -1 -1 0.000 1 0.0000 6300 4500 2160 2160 6300 4500 8460 4500
+1 3 0 2 0 7 50 -1 -1 0.000 1 0.0000 6300 4500 2250 2250 6300 4500 8550 4500
+2 2 0 2 0 7 55 -1 -1 0.000 0 0 -1 0 0 5
+	 6255 810 6345 810 6345 3150 6255 3150 6255 810
+2 2 0 2 0 4 60 -1 20 0.000 0 0 -1 0 0 5
+	 6255 900 6345 900 6345 2250 6255 2250 6255 900
+2 1 0 2 0 7 45 -1 -1 6.000 0 0 -1 1 1 2
+	0 0 2.00 90.00 90.00
+	0 0 2.00 90.00 90.00
+	 6300 4500 7830 2970
+4 0 0 40 -1 18 12 0.0000 4 150 765 6075 450 Fx = 0 N\001
+4 0 0 40 -1 18 12 0.0000 4 195 990 6075 675 Fy = Fz-Fg\001
+4 0 0 40 -1 18 12 0.0000 4 195 705 10125 4455 Fx = Fg\001
+4 0 0 40 -1 18 12 0.0000 4 195 690 10125 4680 Fy = Fz\001
+4 0 0 40 -1 18 12 0.0000 4 195 690 1800 4680 Fy = Fz\001
+4 0 0 40 -1 18 12 0.0000 4 195 765 1800 4455 Fx = -Fg\001
+4 0 0 40 -1 18 12 0.0000 4 150 765 6075 8550 Fx = 0 N\001
+4 0 0 40 -1 18 12 0.0000 4 195 1050 6075 8775 Fy = Fz+Fg\001
+4 0 0 40 -1 18 12 0.0000 4 105 75 6840 3735 r\001