When Gilligan comes to see Ginger to have his fortune told, he breaks her crystal ball. The Professor tells him that Ginger can still predict the future by having a séance. At the séance, the crystal ball is on the table with no breaks or cracks.
At the séance, the castaways are all seated around the table with a table cloth covering the top of the table. When the Professor is seen elevating the table from underneath, none of the castaways' legs/feet are seen nor the tablecloth...just trees in the background. In reality, the castaways and tablecloth would be seen from under the table.
When Gilligan and Skipper argue, Gilligan then leaves their hut carrying suitcases full of the Howell's belongings. Gilligan goes to their hut and dumps the suitcases there. Later Gilligan is seen carrying suitcases full of Mary Ann and Ginger's belongings. Two of the suitcases are the same suitcases he just dumped in the Howells hut: the blue suitcase and the brown with gold braid motif on it.
The Professor incorrectly attributes the quote: "Oh what a tangled web we weave when first we practice to deceive." to Shakespeare. It was actually made by Sir Walter Scott.
If, as Ginger states, the island has tremors "all the time" Gilligan should not have been so shocked by it.
The Skipper tells Gilligan that he doesn't believe in magic that's not true because in two previous shows the Skipper is very superstitious.