Other mistake: Mrs Kenton and Sylvia can't get into the study where Mr. Kenton is; there is no reason why the door would be locked. A mule can't lock it with a key and there is no debris or furniture to block the door. Harold opens it just fine from the inside without operating any particular kind of lock.
The Brass Bottle (1964)
1 other mistake - chronological order
Directed by: Harry Keller
Starring: Tony Randall, Burl Ives, Barbara Eden, Kamala Devi
Revealing mistake: When the genie (Burl Ives) moves the fire plug you can see a bracket holding it up and running down to a track beneath it.
Fakrash: Select the design you wish and 3,000 houses will appear before your eyes...an entire city.
Harold Ventimore: You can't put up houses like that!
Fakrash: Oh, yes I can! With one wave of my hand.
Harold Ventimore: Listen, Mr. Fakrash, you don't own this land. And even if you did, you can't build on it without a building permit. Then detailed plans have to be drawn up, then the building Inspectors have to OK them, then they have to approve every step of the work: foundation, plumbing, electrical... Furthermore, all materials must be union made and all work must be done by union labor.
Fakrash: When the Pharaohs put up the pyramids, they had no such problems. In those days...
Harold Ventimore: - These aren't those days, they're these days. There is no room for magic now. Everything must be done legitimately today. (01:10:00)
Trivia: Harold's quote to Fakrash "What we obtain too easily we esteem too lightly and it has little value" is in fact a famous utterance by Thomas Paine (Dec 23, 1776) that reads: "What we obtain too cheap, we esteem too lightly: it is dearness only that gives every thing its value."