Cambridge Main St. Subway, walls and well found in 1910 while excavating for Harvard Sq. station, 1912, with Letter from Edward Dana to S.E. Morison, 15 March 1934

Second copy of the previous blueprint. Also includes a 1934 letter from Edward Dana of the Boston Elevated Railway Public Trustees to Samuel Eliot Morison, Editor of The Tercentennial History of Harvard University responding to Morison's request for additional information about discovery of early Harvard building foundations during the subway construction excavation in Harvard Square.