Shear waves recorded at five stations in the Maine Seismic Experiment of 1961 are studied to find a possible velocity distribution. Possibilities in various cases are examined based on time, apparent velocity and amplitude, and compared with the results from P. Flat layer models are rejected and the continuous velocity change is the only possible case except for some more complicated structure. The range of possible distribution of S velocity and Poisson's ratio are obtained. The P and S wave crustal models cannot be reconciled with a constant Poisson's ratio. The Poisson's ratio is 0.255-0.27 at the surface and is constant or slightly decreasing up to 15 km deep. Beyond 20 km it increases continuously with depth up to 0.30-0.32 at the bottom of the crust. This implies the continuous change in material in the lower crust.

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