This city is immediately north of Boston and for many years was served by the Boston Edison Company. The latter always preferred glass insulators for their primary and secondary electric lines, exclusively of the deep groove double petticoat "hat" styles, notably CD 164s, 165s, 165.1s + CD 167s. This practice apparently was standard with the company since around the 1910s owing to the abundance of CD 164 Brookfields used (and many still in service) upon their electric distribution openwire. Although their CD 164 Hemingrays have drip points, interestingly the CD 164 Lynchburgs they purchased in the early 20s had smooth bases, probably upon special order. From my longtime experience hardly any CD 162s and any kinds of single petticoat insulators were used by Boston Edison. They operated within Boston and its suburbs, and became NStar Electric about ten years ago. On 4kv primaries and openwire secondaries NStar transfers the old glass upon the new crossarm during pole changeovers ;-)