Leaping of the Shrew - September 27, 1956 - S5-E3
Factual error: On the island, Vanessa sees Venus in the sky and it looks very dark. The other shots show the sun is still up so the Venus sighting wouldn't look like that.
Nowhere to Run - August 10, 1968 - S5-E4
Factual error: Twice in this episode, characters refer to the Vietnam war being over. But the setting is 1968. The Vietnam war didn't end until 1975. (00:34:20)
Goodbye Norma Jean - April 4, 1960 - S5-E18
Factual error: Sam leaps into Marilyn Monroe's chauffeur in April, 1960. But the car he's driving her around in is a 1961 Lincoln Continental convertible. The 1960 had prominent tail fins, the redesigned '61 did not, so the difference is noticeable. This is a model Marilyn could not have purchased until, at the earliest, September of 1960. (00:03:00)
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.