Indentation hardness tests were made on sections of 211 pieces of Douglas fir and 208 pieces of Western hemlock at a moisture content of about 11 percent. Specific gravity and visual-density evaluations were also determined. Correlation coefficients for linear regression of density, as measured by specific gravity, on average standard hardness were 0.826 for Douglas fir and 0.842 for Western hemlock. Classification according to specific gravity was better using hardness classes compared to using visual-density classes. / Graduation date: 1967