The first time we see Midas, West and Gordon take the serum, all three of them wince as a spasm indicates that the formula is taking effect. Later, when Midas and West both take the elixir before their fight, they show no visible sign of it taking effect.
When Thaddeus Baines first arrives at the railroad car, the arrangement of the billiard balls on the table changes between the time Thaddeus Baines first stands next to the table and the time West makes his shot.
Between the time Jim and Artemus are discussing disappearing diamonds around the billiard table and the arrival of Thaddeus Baines, the position of the billiard balls change. Jim would have had time to make a shot, but the tell-tale click of cue-on-ball or ball-on-ball is never heard.
The bars begin to close when Jim and Artemus begin to decelerate up to a certain point, the shot cuts to Morgan and back to Jim and Artemus, and the bars are more open than previously and begin to close again.
When Midas appears next to James on the stairs after hitting Artemus from their position James should have instinctively punched with his right fist. Instead he clumsily strikes out with his left clearly missing Midas even if the latter was not moving at an accelerated speed.
At 37:40, Midas releases a flask at shoulder height in mid-air to show how slowly it falls. A second shot then shows it dropped to his mid-waist. However, when he grabs it back, the bottle is now above his shoulder.
When Midas releases the flask, he says it is falling at 32 feet per second. He should have said 32.2 feet per second per second. In the quarter of a second he says it takes to steal the diamonds, the flask would have reached a speed of eight feet per second.
A diamond does not burn as such; if one is exposed to a temperature of approximately 1300 °F in air, (3,600 °F in vacuum or oxygen-free atmosphere), it turns to graphite, a form of carbon that is one of the softest minerals known. At a temperature of 6600 °F, it goes directly from a solid to a gaseous state.
There is nothing special about the physical properties of a diamond that would make it impossible to use another form of carbon for a chemical reaction. Hence, Morgan Midas could have as easily obtained the carbon he needed for his elixir from pencil lead, since the temperatures he uses (4000 °F) would change the diamonds to graphite anyway as a byproduct of his process.
Just before the final fistfight between West and Midas (Robert Drivas), West asks Lucretia (Christiane Schmidtmer) to toss him a pistol. She does so, however, just as West and Midas begin to "accelerate," and the pistol appears to become frozen in midair. When the effects of the acceleration wear off, the pistol simply drops to the floor immediately where it supposedly became "frozen." From West's point of view, however, the pistol should have continued on its arc from where Lucretia tossed it to where West had originally been standing.
While Jim, Artemus & Morgan are standing next to the diamond case in their accelerated state, a man in the background moves considerably and a woman blinks a moment later.
Lady Margaret's safe has no locking mechanism and once the door is open it is obvious it is made of wood.
When Jim and Artie are setting up the seesaw to go into the Midas house, Artie climbs a fence to jump off and propel Jim up through a window, we see the rigging holding the false sky as the camera pans up to Artie ready to jump.
When West, Gordon, and Midas take the elixir in the carriage, they exit the carriage through the door covered by a curtain. The curtain should have remained suspended after they exited the carriage. Instead, the curtain falls into place as if it were moving the same speed as West, Gordon, and Midas. In addition, the carriage rocks normally as they step down to the ground.