Selected contributions to ground-water hydrology by C.V. Theis, and a review of his life and work

A Primer on Anisotropy" in the early 1970's to provide a tool to those hydrogeologists not conversant with tensor mathematics for the analysis of problems dealing with anisotropic distribution of hydraulic conductivity. At least one reviewer of the manuscript then felt that the treatment was too complex to be considered a "primer," but Theis looked upon it as an elementary technique that was far from "state of the art," even at the time. It is interesting to note that this, his last truly technical paper, is drawn to a great extent from the physical analogy with crystallography, whereas his best-known work, first published in 1935, "The Relation Between the Lowering of the Piezometric Surface and the Rate and Duration of Discharge of a Well Using Ground-Water Storage," was based on another physical analogy, the unsteady flow of heat in a homogeneous solid.