Electricity circuits were placed atop the pole you see on the left with telephone subscriber lines on the 10-pin crossarm beneath (very likely owned by New England Telephone and Telegraph Company at the time).

Note the crossarm affixed above in between the two entrances. Wires led to the insulators upon them, most likely for interior bridge lighting.

This photograph was taken before the commonplace use of automatic photoelectric lighting controllers. So it is likely there were manual switches at each entrance to provide interior illumination with some sort of sign for travellers to kindly shut them off upon departure.

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