This paper presents the Arabic text, the French translation and an analysis of al-Sijzīʼs treatise (second half of the tenth century), the Book of Measurement of Spheres by Spheres. In this text, al-Sijzī divides the cube into several sub-cubes and parallelopipedes, thus offering us a stereometric interpretation of algebraic identities of the third degree usually credited to mathematicians of the sixteenth and seventeenth centuries. However, this was not al-Sijzīʼs motivation for writing this treatise; rather it was his theoretical interest in the Euclidian concept of the “power” of a segment, an interest which is clearly geometric rather than algebraic. This has led al-Sijzī to the notion of dimension, at least in outline.