Factual error: When Janet Leigh is shown lying dead on the floor of the shower, there is a close-up of her open eye. The pupil is contracted to a pinpoint (obviously due to the bright lighting) where it should have been dilated. After the film was released, Hitchcock heard from several ophthalmologists who pointed this out and suggested he use belladonna eye drops in the eyes of "dead" people in future films, as the chemical prevents the pupils from contracting. (00:48:30)
Factual error: Here's a big historical mistake. The character of German Admiral Lütjens is depicted overall in this film as a wild-eyed Nazi fanatic. In real life, he was distinctly anti-Nazi, vehemently protested the anti-Semitic actions of Hitler's regime, and was himself subject to intense Nazi scrutiny as he was a quarter Jewish and his wife was half Jewish. He was one of many German naval officers who fought only for their country, not Hitler.
Factual error: Approximately 2 hours and 10 minutes into the "restored" full-length video version, there's a birthday party for little Lisa Dickinson, and the Alamo defenders sing "Happy Birthday" to her. The Alamo battle happened in 1836. According to David Ewen's "All the Years of American Popular Music," the song "Happy Birthday to You" was composed and copyrighted by sisters Patty and Mildred J. Hill, first as "Good Morning to All," in 1893.
Factual error: When one of the men visits a doctor and learns he is terminal, the X-ray in the scene is upside down.
Factual error: The weaponry of the Romans and their use is wrong (as they are in all Hollywood movies playing in the Ancient Mediterranean that I know): Instead of one spear, each legionary would carry two weighted javelins, called Pila (singular: Pilum), which had a long narrow iron head. The purpose of these were to throw them at the enemy before melee; if they did not kill their targets, the pila would get stuck in their shields. The head shaft would bend, making the pila useless for 'return' to their original owners, and with the added weight of the javelin, the enemies' shields were rendered useless as well. Following this, the Romans attacked with short swords (the Gladii; singular Gladius).
Factual error: In the scene where nickels fall on newspapers announcing that Roosevelt beat Hoover, at least one of them appears to be a Jefferson. The election occurred in 1932. The first Jefferson nickel was minted in 1938.
Factual error: Throughout the movie, characters refer to the "Air Force", when in this time frame (1942-3) it was the "Air Corps".
Factual error: As the machine is traveling through time George becomes aware of "strange sounds" which, when he stops, turn out to be air raid sirens. At the speed at which he was traveling through time, the sirens would have had to operate continuously for several days in order for him to have been able to hear them.
Factual error: Considering the list of the ship (how far it's tilted in the water), its not until they make it to the upper deck that the passengers start acting as if the ship is tilting. Before they get to the top, they are walking normally, and the water is perfectly level with the floor.
Factual error: The plateau blows up because of a volcanic explosion, but the explosion looks nothing like a real eruption. First of all, the plume would be a darker colour, mostly dark grey, and second, the explosion would fly out of the tube the group came out of, so they should still be running, not resting. Also, there would be danger from pyroclastic flow, and lava runoff.
Factual error: In the scene where Elizabeth Taylor is driving from New York City to Boston to start a new life, she drives over the Tappan Zee Bridge, from the Westchester County side toward the Rockland County side (heading east to west, you can tell from the location of the toll booths and from the way the bridge looks.) If she had left NYC by the Lincoln Tunnel, she would have had to cross the bridge going west to east. If she had left NYC via the Bronx, by far the more direct route, she shouldn't have gone over the TZ Bridge at all.
Factual error: The prison in this film, Huntleigh prison, can't be very secure as the hinges are on the inside of the cell doors and the front gate opens directly into the exercise yard.
Factual error: When the two scholars are in the carriage, they mention being 6-7 versts from Mirgorod, and that means that they will be probably late for the inauguration but still able to make it to the conference "in the evening", in Moscow. That is, if they don't waste time dining at the inn. A little rest seems the last of their problems: while Mirgorod (Myrhorod) is certainly closer to Moscow than Moldova, mentioned before, it's still nearly 900 kms, over 850 'versts' if you will! That's a trip they would make in a week, being optimistic, surely not in a day or overnight.