Geometry, Relativity and the Fourth Dimension by Rudolf Rucker
Finding a perfect analogy in the situation of the geometrical characters in Flatland, Professor Rucker continues the adventures of the two-dimensional world visited by a three-dimensional being to explain our three-dimensional world in terms of the fourth dimension. Following this adventure into the fourth dimension, the author discusses non-Euclidean geometry, curved space, time as a higher dimension, special relativity, time travel, and the shape of space-time.
Dover Publications, 1977.
ISBN: 9780486234007. 133 pp.
Softcover. Very good.