Here is what I know about the line that used the Fred Locke "gutter spools"...

From a 1905 article on electric railroad line construction. "Bloomington, Pontiac, & Joliet Electric Railway. Figs. 20 to 24. This line will be 90 miles long, connecting Bloomington and Joliet, Illinois. A section of the line was put into operation February, 1905. The trolley pressure is 3300 volts, and the wires are held in place by catenary construction..." There is an illustration of the pole construction used along most of the line, which is fairly uninteresting. What is more interesting is this figure, which is titled "Cross suspension for high tension trolley. City streets." For a close up, [id=79236269]