May Cover

Reprinted from "Crown Jewels of the Wire", May 1996, page 2

Proving brown glaze is beautiful and that porcelain shapes can be intriguing, this trio is living proof. Insulators belong to Bob Stahr and were photographed by John McDougald.                                                    
                                                                                             

The incuse "POSTAL" marking on the U-154 is clear and bold. Many examples of this style (which resembles its glass cousin, CD 151) were found primarily in Illinois and Iowa on lines serving the Postal Telegraph Company. It is a product of Pittsburg High Voltage.

The August 11, 1914 patented by Benjamin S. Purkey of Tacoma, Washington covered a "twist-lock" design. Jack H. Tod explains in Porcelain Insulators, Guide Book for Collectors, Third Edition, "After the insulator is screwed onto the peg, it is backed off about 1/4 turn and the conductor is dropped into the crown slot, and the insulator again screwed down to secure the wire in place. The conductor runs slack-wire through the insulator crown. Specimens are unattributed as to manufacturer but appear to have been made by Pittsburg. This is a 3-piece glaze-weld, two identical, reversible parts at the top glaze-welded to the base part." One should note that the embossing is on the top of the crown of the U-186 and that it contains a spelling error.

Elton N. Gish shares in Fred M Locke, A Biography that U-220A/B (a two piece transposition insulator) was probably the first transposition style manufactured by Fred Locke at his factory in Victor, New York, followed by the simpler one-part U-192A. The insulator can be found with either incuse marking #0-6 or #1-4 on the upper surface of the top part. The May 22, 1894 patent date is Fred Locke's patent for a transposition insulator. CD 204 was his first transposition insulator based on his patent, then two years later he introduced CD 202.