|St. Louis Riverfront, 1858
The vast majority, I would say, are using Murdoch as the spelling. Murdoch Cutoff and Murdoch Ave. are widely recognized streets in the St. Louis area. That being the case, I believe I will use Murdoch as my choice. If John Murdoch wasn't picky about how he spelled his name, I guess I won't be either.
I have wrapped up my active research at this point, following trips to the St. Louis County Library and the Missouri History Museum Library and Research Center. I may do a little more newspaper research down the road, depending on how the writing comes together. And I need to followup with a source that was listed in another book I found online, but I am ready to formulate the outline for the paper/book. My working title is John Murdoch: the Man Behind the Myth.