Most if all of these appear to be CD 165.1 Whitall Tatums. These along with other double-petticoat, deep groove insulators in *glass* became standard with Boston Edison Company construction commencing in the mid to late 1910s. Single petticoat glass insulators were discarded upon pole changeovers, etc. While other utilities (both public and private) were moving toward porcelain pintypes, Boston Edison preferred with glass through the late 1960s. After that time glass insulators still were used (and still are upon changeovers) (the present company is Eversource). As I witnessed into the 1980s glass pintypes in large numbers were still being stored as active inventory at Boston Edison facilities. Beyond that time light gray cabletops have been utilized in various locations, probably with glass still in stock. Former Boston Edison territory has LOTS of 4kv primary distribution. Pole upgrades still often employ the glass from the previous pole. Most are CD 164 Brookfields, Gayners, Stars and Lynchburgs (these with only smooth bases) as well as Hemingray-20s (SDPs), No Name 38-20s, Armstrong CD 167s in clear and other commonly encountered types such as Whitall Tatum No. 5s. Not much (if any) for rare stuff or anything other than deep-groove double-petticoat glass side-tie designs other than Kimbles that were used for higher voltage (notably 13kv) builds. I do not know why the company always prederred glass insulators. But some others did, such as Pacific Gas & Electric.