These circuits were owned by the Electric Light and Power Company of Abington and Rockland. Abington is about 25 miles SE of Boston (and is my home town). The company's electric generating station was about a half mile from where this photo was taken. The majority of deep amber CD 134 T-H.E. Co. insulators have been found in Abington and neighboring Rockland, all on fire alarm lines, during the 1960s and 70s.