THE PEJEPSCOT HISTORICAL SOCIETY offered tours and Civil War-era re-enactments throughout Brunswick this weekend in commemoration of the 150th anniversary of the Battle of Gettysburg. Here, a re-enactor of the 3rd Maine Regiment joins an encampment on the Brunswick Mall on Saturday. A walking tour of the Bowdoin College campus and its buildings, highlighting Joshua L. Chamberlain’s lifelong involvement, also took place this weekend. As a student, professor and, later, president of the school, Chamberlain left an indelible mark on Bowdoin, and Brunswick.