Abstract
A theoretical study is made of a fairly simple model of an elastic solid in which losses are attributed to both the shear modulus and the bulk modulus. Each of these elastic parameters is represented by a circuit containing two springs and one dashpot. This is a modification of the usual Kelvin solid that has finite stiffness at infinite frequency. The four relaxation times introduced in the model are determined to fit the experimental data presented by McDonal et al. (1958). It is shown that one can obtain a very good representation of their experimental data with the model described above. The wave equation for an elastic solid is given in a canonical form so that one can compare easily the behavior of different models of the elastic parameters.