Factual error: When the whore is talking to Lily, she says "The first thing she should do (in her new tent) is to get the carpenter to lay some boards, or she will be saying hello to Mr. Trench Foot", referring to the medical issue related to feet in wet and unsanitary conditions. This disease of the feet was not referred to as this until World War One. (00:23:10)
Revelations - S1-E7
Factual error: During the race between the horse and the train, the horses are wearing shoes. The Native Americans had no way of forging steel to make horse shoes.
Factual error: In the scenes where they show the flag it's a modern day 50 star flag.
Continuity mistake: At the end of the previous episode, when Mei's father Ah-Tao dies she touches his face (after Buchanan joins the room) and she is wearing dark red fingernail polish with jewels. At the beginning of this episode showing the same scene, Mei no longer has polish on her nails.
Blood Moon - S2-E9
Factual error: The package that Lily gives Elam has a modern day computer printed postage label. (00:32:12)
Factual error: Immediately after Cullen Bohannon is blown out of the blasting hole and is helped up off the ground, a footprint is in the dirt/snow on the ground behind him is revealed that is made from a modern shoe. It's a complex impression made from a cast rubber sole of some sort. (00:15:10)
Other mistake: The "Construction Manager" being the boss of three men makes $125 a month, but the 3 of them make $15 a day working, which is $150 a month. How can the boss make $25 a month less? Even if the three did not work on Sundays... they would still make the same or more than their boss... "Three good men? Them plus some Jakes, yeah. Next time you want a favor, spare me the song and dance, Mr. Strobridge. (Bangs table) They're capable. They are dead weight. Expensive dead weight, at a time when I need all of my resources focused on breaking through that tunnel. And Jim, Charlie Crocker found you five years ago. You were digging ditches in San Jose for pennies a day, and you make $125 a month as construction manager for the greatest enterprise in the history of America. All I'm saying is, $15 a day means a whole lot more to those men than it does to this enterprise." (00:14:30 - 00:15:00)
Suggested correction: The three men make five dollars a day each for a total of fifteen dollars the railroad has to pay.