Bert Kirkland spent many years searching the Collins Line in British Columbia. He made maps indicating the pole spacing, what artifacts he found, and what insulators he found and when. Every so often, he would find a threadless and threaded EC&M at the same pole location. It took him years to realize there were TWO lines with different pole spacing. The original 1865 line was replaced years later when the Dominion Government took over the line and re-built it with threaded insulators, mostly EC&M's. So, Bert went back over the same ground again, with this shorter pole spacing and found the locations of the second line's pole bases.