Factual error: All of the Lydia's lieutenants are wearing epauletes on their left shoulders.only lieutenant commanders were permitted to wear one on the left shoulder, while the right shoulder was reserved for captains of less than 3 years' seniority.
Factual error: The film is set in 1807 and Arthur Wellesley is referred to as the Duke Of Wellington. He didn't become a Duke until 1814.
Factual error: As the Natividad appears, the lookout signals "ship's royals horizon, southeast" by using a shuttered lantern and morse code.unfortunately, neither the lantern nor the code had been invented in 1807. Flag hoists during the day, and rockets and flares at night were the methods of signaling at that time.
Lt. Crystal: Signal from the lookout, sir. Natividad's gone about - one more tack and she'll be at the harbor mouth.
Capt. Horatio Hornblower, R.N: Very good, Mr. Crystal. Well, gentlemen, that leaves time for a rubber of whist.