"Councillor Barklie gave notice that he would move at next meeting that the Council be recommended to change the name of Mustard Street to Library Street and the name of Little Donegall Street to Telegraph Street". (19th August 1891). The street gets its name because it led to Belfast Central Library, which was opened in 1888.
"that the Council be recommended to change the name of Mustard Street to Library Street and the name of Little Donegall Street to Telegraph Street and that Mr Wm. N Wallace be requested to say if he has any objection to the Council's proposal". (Improvement Committee, 26th August 1891).
Mustard Street had received its name from Richard Callwell’s mustard works opened in 1790. The street was marked and named on Williamson’s 1791 map of Belfast. The mustard works only operated until 1798 but the street-name persisted until 1891, at which time it was renamed after the newly opened library. The area was originally known as “Casper Curry’s Meadow” and was the site for “Pepper Hill Steps“.