Encyclopedia Appendex B - Junior Officers
Junior Officers were the young officers of the Navy. They were men who, if they survived long enough, would probable command a vessel of their own. These officers were learning the basics of ship-handling, navigation, tactics, and strategy; in general, how to command a ship. This is the smallest category, there being only two officers.
Master's Mate - were the most senior of non-commissioned officers on the entire ship. Master's Mates had either joined the Merchant Service and received their rank there, or had previously been Midshipman in the Navy. They were generally well experienced in the workings of ships and in the more complicated points of navigation. Master's Mates were training to be either a Sailing Master or taking the examination to become a Lieutenant. Unlike the Midshipmen, Master's Mates did not sit classes on navigation with the captain and/or first lieutenant, but with the ship's Sailing Master. Captains would often allow Master's Mate on larger ships to stand their own watch's, however, on smaller ships it was mandatory, due to lack of officers. In small vessels like cutters, sloops, and the like, a Master's Mate could be the ships Sailing Master and a Lieutenant because of the need to fit as many officers into as few men as the confines of the ship would allow.
Midshipmen - were the quintessential officers-in-training. They were learning the arts of ship-handling, navigation, and command of men. Midshipman, were often first-time voyagers and had much to learn. Many had come from small towns far inland, and had never even seen the ocean. Some, however, had gone to sea at an age deemed too young to be an actual 'officer', and were given the rank of Volunteer (1st Class). These Midshipmen had somewhat more skill than the ones fresh from land. Boys of a wealthy family that wanted their son’s to go to sea, might also send them to the Naval College to learn the basic math skills, as well as other basic principles of the Navy. Before a Midshipman could sit his examination for Lieutenant, he had to served a minimum of six years at sea. Though, "Cooking the Books", when a captain enters a youth into his muster books without the said person actually aboard, in order to gain sea time, was not uncommon, despite its being a court martial offence. Some senior Midshipmen were allowed to stand the occasional watch to help them advance their experience, it also looked good at the Lieutenants Examination.