We began this project in 1968 to fill a gap we each felt acutely after several years of teaching introductory solid state physics to Cornell students of physics,chemistry,engineering,and
materials science.Inboth undergraduate and graduate courses we had to resort to a patchwork array of reading assingnments,assembled from some halp dozen texts and treatises This was only partly
because of the gread diversity of the subject ;the main problem lay in its dual nature.On the one hand an introduction to solid state physics must describe in some detail the vast range of real
solids,with an emphasis on representative data and illustrative examples.On the other hand there is now a well-established basic theory of solids,with which and seriously interested student
must become familiar.