Master's Mate

Master's mate is an obsolete rating which was used by the Royal Navy, United States Navy and merchant services in both countries for a senior petty officer who assisted the master. Master's mates evolved into the modern rank of Sub-Lieutenant in the Royal Navy, while in the merchant service they evolved into the numbered mates or officers.

Originally, a master's mate was an experienced petty officer, who assisted the master, but was not in line for promotion to lieutenant. By the mid-eighteenth century, he was far more likely to be a superior midshipman, still waiting to pass his examination for lieutenant or to receive his commission, but taking rather more responsibility aboard ship. Six master's mates were allowed on a first rate, three on a third rate, and two on most frigates.

Master's mates was a rating for experienced seamen, and were usually selected from the ranks of the quartermasters, who they supervised, or from the ranks of midshipmen who wanted more responsibility aboard ship; they were less commonly selected from other mates of warrant officers and able seamen. Master's mates were allowed to command vessels, walk the quarterdeck, and mess in the gunroom with the other warrant officers.

Master's mates were responsible for fitting out the ship, and making sure they had all the sailing supplies necessary for the voyage. They hoisted and lowered the anchor, and docked and undocked the ship. They would examine the ship daily, notifying the master if there were problems with the sails, masts, ropes, or pulleys. They executed the orders of the master, and would command in his place if he was sick or absent.

Normally master's mates worked on a three-watch system, with the lieutenants, so that one served as the deputy to the lieutenant on each watch. Master's mates generally assisted the master in navigating the ship and directly supervised the quartermasters in steering the ship. The master's mate with the highest seniority was appointed the head of the midshipman's berth and was responsible for teaching mathematics, navigation, and sailing lore. Master's mates had to keep detailed logs similar to midshipmen. They were also responsible for the division of the crew that included the petty officers.

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