As in “The Playford Ball” Longways for 3 couples
Peter Thompson, 1765
Video: https://www.youtube.com/watch?v=Wpyl54cXFPk
(This Swedish video chosen because it shows the geometry pattern of the dance, though the dancers are rather wooden and trying to dance on stone pavers that are slippery!)
Recordings: shrewsbury_lasses--009.mp3.zip
shrewsbury_lasses-bnah5-06.mp3.zip
shrewsbury_lasses-054-engech-11.mp3.zip
shrewsbury_lasses---010.mp3.zip

A1 1-4   1st man slow set and honor, right, then left, to 2nd woman. 
   5-8   1st man turn 2nd woman two-hands.
A2 1-8   1st woman the same to 2nd man.
B1 1-2   1st couple cast down to middle place, 2nd couple moving up.
   3-6   1st and 3rd couples circle four-hands once around.
   7-10  1st man skip up outside and around top couple, 
         to end in middle place improper whlle 1st woman skip 
         down outside and around bottom couple, to end 
         in middle place, improper. 
   11-12 1st couple turn two-hands half-way.
B2 1-2   3rd couple cast up to middle place, 1st couple moving down. 
   3-6   3rd and 2nd couples {at top} circle four-hands once around.
   7-10  3rd man skip up outside and around top couple, to end 
         in middle place, improper whlle 3rd woman skip down outside 
         and around bottom couple, to end in middle place, improper. 
   11-12 3rd couple turn two-hands half-way.
   Repeat dance twice more

See an animation of this dance.

From John Garden, who gives an AAB arrangement of the tune as the music for a triple minor.

Shrewsbury Lasses to own tune

A triple minor longways dance from Thompson, Twenty-four Country Dances 1765 and (text used) Thompson's Compleat Collection, vol.4, 1780.

   A1 First Man set forward to the 2d Wo. ,
      turn single back to place over r.sh. 
      then come forward to take hs with corner 
      and turn all the way round with 8 steps, starting r.f.)
   A2 1st Wo. do the same with the 2d Man
   B  With 12 steps 1s Cast off & hands round four with 3s at bottom. 
      With 12 counts of skipping The Wo. go cw round the bottom Cu. 
      the Man cw round the top Cu. ('orbits below and above') to meet 
      improper in the middle and turn (partner with 2h 1/2 way) into 
      your own Places in progressed position, 1M, by releasing his r.h. 
      before his l.h. can open out easily to face new 2W or, when one 
      place from end of set and needing to go to the bottom, the 1M&1W 
      can let their 1/2 2h turn send them out behind and around the couple below them.

This dance was possibly used by the P&P director for the dance between Mr Collins and Lizzy as it gives Mr Collins a very good opportunity to go wrong…. but recover. The Apted editors change the dance to a 3 couple dance, with an additional B music to repeat the “chase” and progress the couples.