Passed midshipman

Between 1800 and 1815, due to a shortage of officers to command small craft, passed midshipmen were titled sub-lieutenant but this also was not an official rank.

[1] A midshipman who became master's mate earned an increase in pay from £2 15s to £3 16s per month, but initially reduced his chances at a commission.

These changes helped eliminate the confusion caused by the mingling of midshipmen in the navigator's branch.

[4] In 1838 a Royal Commission, presided over by the Duke of Wellington, recommended the institution of the rank of mate as an official step between midshipman and lieutenant.

A passed midshipman would be appointed a commission to the rank of ensign, rather than lieutenant.

Shoulder straps used by passed midshipman T.R. Young on the USS Brandywine . The shoulder straps were tied on to the uniform coat with shoe strings. The straps are circa 1860s.
Midshipmen studying for their Lieutenant's examination aboard HMS Pallas . Sketch by Gabriel Bray, 1774