Davidson & Stevenson Porcelain Co. was in operation from 1913-1920. Their address and city indicated in the 1918 catalog was East Liverpool, OH because the sales office was located there, but the plant was located across the river in Newall, WV. In 1920, Stevenson left the business and the company name was changed to Davidson Porcelain Co. The company closed in 1936. D&S made a full line of Standard Porcelain knobs, cleats, and tubes. The 1918 catalog showed two pages of wet process porcelain pin-type insulators. We believe they first made pin-types in dry pressed porcelain most likely in the earlier before 1918. We suspect the following dry pressed insulators were made by D&S based on the characteristic embossed circle at the top of the pinhole. The U-151A has this embossed circle and shiny black and tan glaze. I have one with a rust/mustard colored glaze. Some dry pressed U-15's have the tan or black/tan glaze with embossed circle, but the one I have does not have the circle. I have a U-709A I got from Bob Stahr which is dry pressed with the circle and nearly black glaze. However, U-625A with an embossed circle and incuse marking B166 is a wet process insulator. We do not know for sure if any of these insulators were made by D&S. While the beehive in the 1918 D&S catalog looks similar to U-151A, it is a wet process style. None of the insulators shown in the 1918 catalog or the more modern styles shown in the later Davidson Porcelain Co. catalog have been reported. One of the photos shows 3 different U-151A's. [id=176814320]