Keep in mind that just because it's posted on the internet or in print like Roger K. Smith's Patented Transitional and Metallic Planes in America 1827-1927 Volume I &II doesn't always mean that it's true. I think a lot of misinformation about Union Hand Planes made by Union Mfg Co and their subdivision has been propagated by Roger K. Smith's book. At the time he published it and based on all of the people that provided information he believed it to be true.
Public Domain, https://commons.wikimedia.org/w/index.php?curid=520482
By ZeWrestler - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=21667908