Near the end when Artemus breaks into the front door where Mark has placed a chair, when the door is forced open you will see that the curtain goes through the window. The were no window panes in the door.
The phrase "So help me Hannah" did not appear until the 1920s.
Lucas goes to find the body of the dead man Mark tripped over covered with leaves. He brings the body back to the ranch, walks in and sits down to eat, grabbing bread without washing his hands. Lucas always taught Mark good hygiene.