"This pre-Einstein geometrical fantasy is one of the best things of its kind that has ever been written, for it is more than an ingeniously sustained fantasy: it is a social satire, with wit as sharp as the sub-lutrous end of a Flatland woman; it is an easy philosophical introduction to the Fourth Dimension; and it is a rebuke to everyone who holds that there is no reality beyond what is perceptible by human senses."
The best introduction one can find into the manner of perceiving dimensions.
****Reprint of the classic essay on the fourth dimension originally published in 1884. Cited in BCL3. Annotation c. by Book News, Inc., Portland, Or.