I’ve been a casual collector of glass insulators for most of my life. Casual because it is on and off, nothing serious. I probably only have about fifty of them in my collection, which is just a pittance compared to real collectors. Below is one of my favorites.
Glass insulators were invented and manufactured in the mid-1800s to attach telegraph lines to wood poles, often along rail road tracks. They succeeded in securely holding the wires, plus they insulated the wires from the wood poles, which if touching could drain some of the electric current. The wires would wrap around the glass insulators securely, then proceed to the next pole. With little to no loss of signal.
Electric telegraph (in the United States) was developed by Samuel Morse in 1837, and the first message was sent by Morse in 1838.
The period from 1875 to 1930 saw hundreds of millions of glass insulators produced. Besides telegraph lines, they were later used with telephone and electric transmission lines.
All, or almost all of these collectable glass insulators stopped being produced about 1967. Today insulators are still used but the design is more advanced and usually not as attractive as the old glass and porcelain ones.
It was in the 1960’s that people began collecting the old glass insulators.
In Idaho there are still plenty of wild glass insulators, still up on the poles following railroad tracks.