Step 1: Choose either one cross cylinder out of two, as the sphere.Step 2: Subtract the cross-cylinder which was taken as the sphere from the other cylinder which was not taken as the sphere in step 1.Step 3: Axis of the sphero cylinder form is the same as the axis of the cross-cylinder which was not taken as the sphere.

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The Cross Cylinder

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Flat Transposition : Cross Cylinder to Sphero Cylinder

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