The meaning of 'vinegar-visage'

[Haihao]

Gentle reader, do you remember Monsieur Poopoo? He used to keep a small toy-store in Chatham, near the corner of Pearl Street. You must recollect him, of course. He lived there for many years, and was one of the most polite and accommodating of shopkeepers. When a juvenile, you have bought tops and marbles of him a thousand times. To be sure you have; and seen his vinegar-visage lighted up with a smile as you flung him the coppers; and you have laughed at his little straight queue and his dimity breeches, and all the other oddities that made up the every-day apparel of my little Frenchman. Ah, I perceive you recollect him now. -THE LITTLE FRENCHMAN AND HIS WATER LOTS by George Pope Morris, The Best American Humorous Short Stories

Hi,

Could you help me with the above underlined parts about:

1. What does the ‘vinegar’ here refer to? Ill temper or liveliness?
2. Does the queue mean braid? But he was a Frenchman!

Thank you.

haihao

[Conchita]

A vinegar face is a sour or angry looking face.

‘Queue’ here means ‘pigtail’, which some men used to wear in the past, too.