Just before Ishmael and Queequeg meet Elijah, they walk past a moored ship which has a Plimsoll mark painted on her hull. The scene takes place in 1841, but Plimsoll marks were not devised until the 1870's.
In the scenes with the Quaker characters, despite Herman Melville's correct use of "thee" and "thou," the two Captains frequently misuse "thee" as the subject, when it is only ever used as the object. For instance, the Peleg and Bildad will frequently say phrases such as "hast thee" or "art thee" when the correct use of this mode of speech calls for "hast thou" or "art thou."
Early at sea (on the Cape Verde grounds) the first whale is spotted and then harpooned by harpooners on each of the three boats. As the whale runs, towing each boat behind him, a call of "man overboard" is made and we see a close-up of a crewman cutting his boat's harpoon line and then another shot of both remaining boats being towed by the whale, but in the next shot, facing forward from the whaleboat's perspective, we see three taut lines leading back from the whale.
When the white whale rams the ship, the main mast breaks and comes down, crow's-nest and all, hitting the cabin boy. The whale circles the ship creating a whirlpool; when we see wider shots of the ship spinning and sinking, the mast is back up.
The way the ship was moved away from the pier was incorrect. The crew is shown hauling a line from the pier. This would not make the ship move forward.
To move a ship out of the harbor, it is therefore, necessary to provide something to pull against. A special anchor, called a kedging anchor, is carried as far from the ship as possible by the longboat and then dropped to the seabed. The remaining crew pull the ship out to it winding the line around the capstan or winch, and then it is hauled up and the process repeated as many times as necessary.
During the scene when the masts and Ahab's harpoon are covered with St. Elmo's fire, the luminous phenomenon was shown as a green glow. Physically, St. Elmo's fire is a bright blue or violet glow, appearing like fire in some circumstances, from tall, sharply pointed structures, so the color of the phenomenon is incorrect.