In 1972, I purchased 17 CD 134 insulators at a local antique store in Boone, Iowa. The owner was a local historian - as most are. The story she told me was that they obtained these insulators in the early 1950's as most of the Boone, Iowa electrical network was upgrade and the oldest system was finally removed from the poles and downtown businesses. The first power plant for Boone, IA was built by the Chicago Northwestern Railroad in 1877 to power their operations. This power plant used local coal as fuel. Shortly after this, a low voltage electrical line was extended to run the electric lights and power local businesses. The homes and some farms in and around Boone were electrified in 1886 to 1890's. The second upgrade took place in the early 1900's and the third upgrade occurred after WWII. Some of the earliest insulators were never removed from some poles and many business until the fourth upgrade in the 1950's.

The first post shows three of the most uncommon to rare insulator [id=614871404] from the lot of 17 insulators purchased. The remaining 14 CD 134 insulators included two deep blue and the rest were various pastel colors. This post shows three of the more interesting common CD 134 insulators.

CD-134 Patent / Dec 19 1871 (Front Skirt) - No Mold Letter - (Minor Bubbles & Microbubbles) Deep Blue - 73mm Wide x 98mm Height

CD-134 Patent / Dec 19 1871 (Front Skirt) - No Mold Number - (Bubbles & Microbubbles) Patel Steel /Powder Blue - 73mm Wide x 98mm Height

CD-134 Patent / Dec.19. 1871 (Front Skirt) - Mold Letter "B" -(Bubbles & Microbubbles) Pastel Yellow Green Cast - 73mm Wide x 98mm Height

Note that all the domes have slight variations. The pastel yellow-green CD 134 is especially unique - it has periods in the date, a different dome slope, a mold letter "B" and slight flare to the skirt. I'm wondering how many different mold styles exist? Out of all the CD 134's the pastel yellow-green was the only one with a mold letter.