The collected works of Ernst Eduard Kummer form two volumes. Volume I is devoted to Kummer's work on number theory while Volume II, divided into four parts, focuses on his other research interests. Part 1 (Function theory) covers his work on the hypergeometric function, and on repeated integrals of rational functions. In Part 2 (Algebraic geometry) we see how the discovery of "Kummer surfaces" seems to have been an outgrowth of Kummer’s interest in the optical properties of biaxial crystals, and in the "Cyclides" of Dupin. The relation between these quartic surfaces and quotients of abelian surfaces was discovered only much later. One also finds here a number of papers describing actual plaster models of particular "Kummer surfaces", with special symmetries in evidence. Part 3 concerns Aerodynamics and ballistics and, finally, Part 4 (Speeches and reviews) spans a broad range of topics, including a long retrospective on the life and work of Dirichlet.