The specific aims for the next year of the study are: 1. Determine the distribution of structural types in the individual osteon and its relationship to degree of mineralization and the spatial location and orientation of the osteonal segment in the bone. 2. Determine the strain rate dependent compressive behavior of osteonal segments and lamellar pseudo osteons as a function of composition and internal structural organization. 3. Develop a predictive model to fit the compositional, structural, and mechanical results to a generalized osteonal structure. Experiments in these three areas are to be continued in year two for the first aim, years two and three for the third aim, and years two, three and four for the second aim.