Page 335. " I have not so much to say for my friend Flora, who jilted a very nice young man in the Blues "
Late 19th century depiction of a Royal Horse Guard (right) in 1815
Public DomainLate 19th century depiction of a Royal Horse Guard (right) in 1815 - Credit: Richard Knötel

 The Blues is the nickname for The Royal Horse Guards, a cavalry regiment of the British Army, founded in 1650.

During Jane Austen's time, it was known as the Royal Horse Guards Blue.

In 1969, the Royal Horse Guards amalgamated with the Royal Dragoons to form the Blues and Royals.

 

Page 349. " They passed the Drawbridge, and entered the town; "
Plaque at the Landport Gate
Creative Commons Attribution Share AlikePlaque at the Landport Gate - Credit: Basher Eyre

 Because of Portsmouth's  strategic position in the English Channel and its naval connections, it became a heavily fortified town, and the old town was walled for a large part of its history. Between 1760 and 1875, the main entrance to the town was via the Landport Gate which was preceded by a moat and drawbridge.