I actually did research for this, and the Captain is one of two things, either the owner of the ship, or the owner and chief officer. Merchant ships more often than not had a separate owner and chief officer, making the Captain more of a passenger who owned the boat and the CO the Skipper (captain for all intents and purposes.) The helmsman(I've edited) drove the boat, so to speak, and worked with the Second Mate, who headed navigation. The Helmsman and the Skipper were sometimes combined, based on the preferences of the Skipper. If not, The helmsman answered to the Acting Captain(CO,Skipper), and the Second mate, but the First mate was in charge of crew and cargo. The Third mate was the Bo'sun, and was in charge of safety on deck. Therefore the Heirarchy, after research and deliberation, would be Captain, CO, First and Second, Then Third/Bo'sun and Helmsman, and then the rest of the crew. If the CO and Captain were one guy/girl, then that first bit was a combined step. Hence Eli does not do skipping, he helmsmans.