Most of the insulators appear to be CD 145s. This line was upgraded either in the late teens or early 1920s with new poles, hard-drawn copper wire, 10-pin crossarms and additional insulators (predominantly CD 152s). Most of the CD 145 insulators were reused along with pole line hardware that was in good condition (nuts, bolts, braces, pins, etc.). Many of the new poles were cedar and a lot of them between Boston, MA and Portland, ME were still standing up until the 1990s.
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