Poletop brackets like you seen on the tilted pole on the left were commonly used here in the US for stringing fire alarm circuits since the early 1880s. In general, these wires were strung atop pole lines so that no other lines (such as fallen ones) could affect (or interfere with) them. Thus protecting these important fire-reporting circuits from going out of service. Some communities used metal brackets of various types. Others employed their fire alarm telegraph crossarm simply as the top arm atop a pole. In addition, wooden crossarms (generally short ones) were sometimes supported upon pole top extensions by using a 4-by-4 or similar piece of wood mounted vertically at the pole's peak.

By the teens most fire alarm circuits were placed lower on utility poles, typically just above the phone lines and beneath electric distribution. Improved line hardware along with safer electric utility construction, practices and codes introduced around 1910 probably led to this.

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