When Edith stops by to check in at her magazine office, the editor's lit cigarette jumps from her left hand to her right hand and back multiple times.
The smoke arising from Laura Edmunds' cigarette is noticeably fake, dissipating almost immediately, like steam. Actual cigarette smoke hangs in the air.
At the motor racing circuit the VOR antenna is shown in the background during some racing scenes. VHF Omnidirectional Ranging wasn't invented until 1937 and was deployed after the second world war.