Wooden clothespins were invented in 1853, but at the 33 min mark, Michaela is seen using rustic wooden twigs to hang washing on a line.
At the 41 min mark, Dr Mike's mother can be seen wearing nail polish that was not invented until the 1920s.
In the Pilot, Charlotte tells Dr Mike that Abigail died on the way to Denver to get a doctor, but as Loren is driving Mrs. Quinn back to the homestead Loren reveled to her that Abigail died at the homestead.