"A treatise of moderate size, clear in method and free from
technicalities of the schools." —Pall Mall Gazette.

"A very solid piece of reasoning in the domain of higher mathematics." —Glasgow Herald.

Models to accompany The Fourth Dimension:—
    81 Cubes and Slabs, 16s. nett; 12 Catalogue Cubes, 21s. nett.

"To say the least of it, the book is a powerful mental gymnastic.
The style is as clear as it can be. The Author is in grim earnest, and
promises a complete system of four-dimensional thought, mechanical,
scientific and aesthetic."—Literary World.

   SERIES I.—What is the Fourth Dimension—The Persian King or
The Law of the Valley—A Picture of our Universe—Casting out the
Self—A Plane World.

   SERIES II.—Education of the Imagination—Many Dimensions—
Stella—An Unfinished Communication.