The fourth post shows a CD 134 C.E.L.CO. insulator as follows:

CD-134 C.E.L.CO. (Front) - (Vapor Milk Streak) Deep Teal Green - 72mm Wide x 105mm Height Most people believe that the C.E.L.CO is the Cambridge Electric Light Company which was an electrical supply house that existed from 1887 to 1892. Most of these insulators are found in the Northeastern part of the country. As far as I know, there is no report of this insulator being found in the Mid-West. Also, the color seems to be unique as most of the reported insulators are blue to aqua. This insulator may be a "Pennycuick" - the threading is right and there is a small knob of glass on the inside of the dome. However, the color looks more like Brookfield glass. Comments are most welcome.