Most of the examples here have been verified by means of hallmarks or other hard documentation. Over the years, there wasn’t a switch that signaled a change in profiles or details. They seemed to evolve over time until they became standard.
James Martin’s departed in the late 1950’s and George Kilgour became shop foreman. I am partial to this bagpipe. The materials and workmanship set a very high standard, not only at that time but across all time. The bass drone of the Robertson bagpipe was not quite as dominant as some other makes, however the balance was very good and they are oh-so-steady.