Linda and Bob Barth, along with Jim Sommerville, have recently published a new photo history book on Somerville. The book, “Somerville Through Time,” features “then and now” images of the town including a number of interior photos of the Wallace House that show its gradual restoration to the authentic historic site we know today. Linda and Bob will be showcasing their work at the Van Horn House as part of the Heritage Trail Sunday Speaker Series, February 7 at 2 pm. The lectures are open to the public and free. Copies may be purchased there or people can order online: People can order online at www.somervillethroughtime.com.