Through a series of dialogues between a somewhat grown-up Alice (of Looking Glass fame), her uncle Lewis Carroll, and a visitor from the 20th century, Dr. Whati... » 

Through a series of dialogues between a somewhat grown-up Alice (of Looking Glass fame), her uncle Lewis Carroll, and a visitor from the 20th century, Dr. Whatif, this work gives an informal introduction to the non-Euclidean geometries. «