These links may have already made it to Icon. Both are about railways, sorry no insulators. The first is building the last 120 mile section of CP track, 1880, along the north shore of of Lake Superior. https://vimeo.com/mcltr/review/224774963/084f872872

This second link I found while researching a property I own in southern Ontario, thru which the GTP track remains are located. The concrete bridge adjacent to my property is dated 1906, and the track was abandoned and dismantled just 20 years later. While the articles give a glimpse into the working life of the era, the video is the highlight. From the air, it follows a 50 mile section of the abandoned track. Filmed in the last 10 years, just watch it and see how easy it is to still locate and follow old railway beds abandoned 100 years ago. If you're the one who hunts old railways looking for them threadless jems, you must watch this.

http://porthopehistory.com/railways/cnor/index.html