Factual error: Between Earth and the Moon the crew of the spacecraft have an EVA in which they walk on the ship's metal hull with magnetic boots. At one point an astronaut inadvertently slips both boots off the hull and drifts off into space, helpless. There is a long shot of him drifting away in which his body spontaneously spins around 180 degrees and then stops rotating, which is all a violation of conserved angular momentum.
Visible crew/equipment: You can see Dean Stockwell's harness and guide wire when Kim is hauled off the ledge and up the cliffside.
Revealing mistake: Having been deserted by their porters three white people and a native journey on. During their journey an antelope is shot by Allan Quartermain for food. The sound of the shot is dubbed in as there is no recoil from the high powered rifle he uses.
Continuity mistake: Jim Hawkins is stabbed in the shoulder, but when the doctor later treats and binds the wound, it has moved to his upper arm. (01:20:25)
Continuity mistake: When Daffy begins reading "The Scarlet Pumpernickel" at the start of the cartoon, you can see that the script is by the wall. Later on, both Daffy and the script are in front of J.L.'s desk, and a few shots later they are near the wall again.