It might be helpful to look at all of the ways Howe used the word "chassee" in his dance manual. This edition actually spells it "chassa" but the word appears at least 40 times: https://books.google.com/books?id=XkJKAAAAYAAJ&printsec=frontcover&dq=elias+howe&hl=en&sa=X&ved=0ahUKEwjyq-DG5rHSAhVE4YMKHViFDiwQ6AEIHDAA#v=onepage&q=chassa&f=false

A variety of words follow it: "chassa round to the left," "chassa across," "chassa de chassa,"chassa croissez," "chassa out," etc. To me, that would indicate that, as now, "chassa" is simply the footwork of a sliding step, with the direction of that step following. I did find at least one example of "chassa across partner," which makes me think that a simple "chassa across" would be across the set.

I did find this description: "All Chassa: Each couple facing their own partner and chassa across each other four steps the gentlemen passing to the outside of the ladies and back the same finishing with a bow and courtesy The gentleman then offers his hand or arm to his lady and conducts her to her seat which is the proper termination to every set of Quadrilles (8 bars)"

The "facing each other" would also seem to indicate that the couples are crossing the set with their partners and not crossing their own partner.

Deborah Hyland

St. Louis