Revealing mistake: Almost every time Sam looks in a mirror or the viewer sees Sam in a mirror, the movements of Sam and Sam's "reflection" hardly ever match up correctly as if it were Sam's real reflection.
Revealing mistake: Al is supposed to be a hologram. However, he is constantly casting shadows, and as a projection, he shouldn't.
Genesis (1) - September 13, 1956 - S1-E1
Revealing mistake: Tom/Sam's wife and her reflection on the mirror do not match. The reflection moves her head, but the real person does not do that. (00:06:40)
Star-Crossed - June 15, 1972 - S1-E3
Revealing mistake: Sam stares at himself in the mirror and takes out his wallet to determine who he's leaped into. But the "reflection" in the mirror lowers the wallet and looks back up before Sam does. (00:05:20)
The Right Hand of God - October 24, 1974 - S1-E4
Revealing mistake: As Sam looks in the mirror, the trainer's reflection puts its right hand on Sam's right shoulder a split second before the camera view hand.
Double Identity - November 8, 1965 - S1-E6
Revealing mistake: Sam's reflection character turns around too slowly in the mirror at the beginning of the episode.
Play It Again, Seymour - April 14, 1953 - S1-E9
Revealing mistake: After Sam nearly falls down the elevator shaft, the scene fades and comes back in with Sam speaking to the landlord about the incident. The landlord brushes off Sam's hat with his hand and hands it to him. The brushing motion was played in reverse first to extend the length of the action.
Play It Again, Seymour - April 14, 1953 - S1-E9
Revealing mistake: Sam opens his left hand when talking to Al at the beginning. His reflection does not. His reflection just points his finger.
Play It Again, Seymour - April 14, 1953 - S1-E9
Revealing mistake: Sam is getting shot at in the aircraft hanger. He hides behind a yellow machine and a bullet hits it. The bullet produces a flash but leaves no mark where it hits. A real bullet would have left a gash at the least.
The Americanization of Machiko - August 4, 1953 - S2-E3
Revealing mistake: When Sam is first looking at his reflection of himself in the glass at the beginning of the episode, the items behind his reflection do not match his point of view. A man walks through the shot and never leaves the frame, however is gone when the shot flips back to Sam.
What Price Gloria? - October 16, 1961 - S2-E4
Revealing mistake: When Sam is getting ready with the other woman, the shoes on the floor do not match in the reflection. Their position is off.
What Price Gloria? - October 16, 1961 - S2-E4
Revealing mistake: Sam and the other woman are staring at their reflections while Sam is getting ready. Notice where the woman with darker hair is standing in relation to Sam. Their mirror images are further apart. The woman with darker hair also has her head tilted to the right slightly. Her mirror image doesn't.
Jimmy - October 14, 1964 - S2-E8
Revealing mistake: When Sam is helping Frank clean his truck, an old couple passes as they are talking. Watch the shadows on the left side of the frame right before they enter. The shadows pause for a second, and then the couple walks on screen as they are being cued by the director.
A Portrait for Troian - February 7, 1971 - S2-E11
Revealing mistake: When the recovered drowning victims are lying on the ground, Troian's supposedly dead husband moves his feet. (00:39:25)
Animal Frat - October 19, 1967 - S2-E12
Revealing mistake: When Sam and Al are walking and talking, just after Scooter (being chased by the dog) throws Sam the dean's prized basketball, Al's shadow is visible on the ground, though as a hologram he doesn't actually have one.
Another Mother - September 30, 1981 - S2-E13
Revealing mistake: When Sam and Al are in the station wagon pursuing the van, both Sam and Al's reflections are visible on the wagon's front hood. Al, as a hologram, shouldn't have one and Sam's reflection should be as Kevin's mom.
Her Charm - September 26, 1973 - S2-E15
Revealing mistake: When driving to the cabin, the mileage markers on the roadside indicate they are in Los Angeles, nowhere near Boston or Baltimore. (00:20:30)
Her Charm - September 26, 1973 - S2-E15
Revealing mistake: When Al is helping Sam find Dana in the forest, his feet keep kicking up or moving the dirt and leaves, which a hologram shouldn't be doing. (00:39:00)
Her Charm - September 26, 1973 - S2-E15
Revealing mistake: At Boston's FBI, Al's reflection is visible repeatedly, such as on the fire extinguisher's chrome surface in the hallway and on the elevator while Sam talks about the cabin.
Good Night, Dear Heart - November 9, 1957 - S2-E17
Revealing mistake: When Sam is talking to the sheriff in the parlor and says it can't be prosecuted, he walks in front of a mirror and we see the real doctor in the mirror, except we see the real doctor standing up just as he becomes visible, and Sam's shoulder just to the left. They used the mirror's angle to fake the mirror image, and probably panned the camera over the other actor's head as it swung around which is why he had to stand up. (00:38:40)
Answer: Sam threw items off the raft to lighten the load, so it wouldn't sink, in doing so he made the raft less heavy. Which made easier to float with the currents, if it was heavy the raft would have moved slower and not moved so far.
Except that Al said that immediately after throwing stuff out of the boat four hours passed and it was shown that they didn't really move from where they were. They were still in the same spot. Forgot to ask this too. When Sam and Vanessa are stranded on the island, one of them, can't remember who, did something and when Al appears, he tells them that because of it, time had suddenly skipped several more hours and if the event hadn't been interrupted, they would have been rescued by a boat. So, what happened on the island that once again caused time to speed up? It seems kind of strange that time could move so quickly on the island, especially since it was still day time and it never showed any sort of changes like the sun or clouds moving.