Black velvet bonnet

From JA's letter to Cassandra Austen, Tuesday 18 December 1798 (Deirdre le Faye 1995 edition, p 25-26):

I took the liberty a few days ago of asking your Black velvet Bonnet to lend me its cawl, which it very readily did, & by whic I have been enabled to give a considerable improvement of dignity to my Cap, which was before too nidgetty to please me. - I shall wear it on Thursday, but I hope you will not be offended with me for following your advice as to its ornaments only in part - I still venture to retain the narrow silver round it, put twice round without any bow, & instead of the black military feather shall put in the Coquelicot one, as being smarter; - & besides Coquelicot is to be all the fashion this winter. - After the Ball, I shall probably make it entirely black.