American Journal of Mathematics, vol. xix. I (Baltimore, January, 1897).—Theorie der periodischen cubischen Transformationen im Raume R3, by S. Kantor, contains a full account (in 59 pages) of the theory on the lines of the same author's Theorie der endlichen Gruppen von eindeutigen Transformationen in der Ebene (1895).—Mr, Basset, in theories of the action of magnetism on light, discusses the theories of Maxwell, Fitzgerald, and Larmor. His object is twofold. First, he subjects Mr. Larmor's theory to a searching examination, and maintains that instead of being an improvement on its predecessors, it is open to a variety of additional objections and defects.