When Bohannon gets aboard the train to take it across the newly-built trestle, the tender has coal in it. Coal wasn't used exclusively in steam engines until 1870. The viewer sees wood in the tenders on all other train scenes.
The railroad ticket Mrs. Durant gives Lily has spaces to write in "From" and "To", but the ticket price has been pre-printed as $135. The cost of the ticket would be variable depending on the distance traveled by the passenger.