B65-755 BILL POSTING HAMMER. A. R. Robertson. Patented in 1902 by Arthur Robertson of Somerville, MA, and described simply as a magnetic tack hammer, these were marketed as being particularly well suited for posting handbills in hard to reach locations. These were typically sold in multiple parts that screwed together, most of them have only two parts but this is the very uncommon three part version. Some overall light wear but no damage. From the collection of David Jeffers. Good+ 150-300