The purpose of this study is to determine how the fluid behaves in stressed cortical bone, primarily because of the importance of fluid behavior in several current hypotheses concerning the effect of stress on bone remodeling. In particular we intend to investigate the relaxation of the fluid pressure when bone is stressed. The electrokinetic properties, permeability and the contribution of the fluid flow to the electromechanical effect and mechanical damping will be measured for fluids of different viscosities and ionic strengths, so that the dependence of the bone properties on the fluid properties can be determined. The electromechanical and damping measurements will be done as a function of frequency in the range 10 Hz to 1 kHz. The data on the damping and electromechanical effect will be correlated with the permeability and electrokinetic data from the same samples to determine the relaxation time for the fluid flow in stressed bone. These properties will also be related to the microstructure of the samples as determined from light microscopy and SEM studies. This data will allow a comparison of the experiments with theoretical models for the decay of the fluid pressure in stressed bone. They will also provide guidelines for further investigations into the possible influence of stress on bone remodeling.