From: http://www.wam.umd.edu/~eowyn/3LF/two.couple.html

Saint Martin's
2 Couple Set Dance, Barnes, Playford 1651.

Appoint a Couple1 ('Fred') and a Couple2 ('Non-Fred') in each set; at the end
of the dance both couples will open out in a line facing toward the Couple1's
right. This dance does NOT follow the standard Playford pattern (although it is
Playford) and is difficult to learn.

A1: Take inside hands with partner, Double Forward, two Slip Steps left, 
    two Slip Steps right. Drop hands with your partner, turn single-out (men
    counter-clockwise, women clockwise) and back (reverse). 

A2: Take inside hands with partner. Single Back, Single Forward. 
    Drop hands, pass your corner on the right, face your partner and pass on 
    the right, end facing into the set. All Turn Single.

B1: Women Turn Single while men Double Back on their diagonal, come skipping
    forward, they turn by the left (3/4) and then turn their corner 1 1/2 
    by the right (continue skipping through the turns). 

B2: Men Turn Single while women Double Back on their diagonal, 
    come skipping forward, they turn by the left (3/4) 
    then turn their partner 1 1/2 by the right returning to place 
   (continue skipping through the turns).

A1: Take inside hands with partner. Single Back, Single Forward, 
    pass through the set. Set and Turn to partner. 

A2: Take inside hands with partner (improper). Single Back, Single Forward,
    pass through the set. Set and Turn to partner.

B1: Men step into the center and make a small reverance, women step into the
    center and make a small reverance. 
    Take hands four and circle clockwise 1/2 way around the set. 
    All Turn Single (traveling out enough to allow space for the next figure). 

B2: Women step into the center and make a small reverance, men step into the 
    center and make a small reverance. Take hands four and circle clockwise 
    1/2 way around the set. All Turn Single.

A1: Take inside hands with partner, Double Forward. 
    Take both hands with corner and single Slip Step out, single Slip Step in. 
    Drop hands. Men will Cast away rom the set, walk through the woman's spot 
    and return home. Women will follow (chase) their partner around and 
    return to place. 

A2: Take inside hands with partner, Double Back. While still facing the
    opposite couple, switch places (woman in front). 
    Men start the Double Forward (moving slightly left) and Double Back 
    (moving more left) so that they pass behind each other), while women 
    Double Forward (moving slightly right) and Double Back (moving more right) 
    so that they pass behind each other. (This figure is basically a do-si-do 
    or a back-to-back except you are switching places with your partner, 
    ending back home).

B1: Men step into the center of the dance, reverence. 
    Women step into the center, reverence. 
    All form a right-hand star and go all the way around (not much time) and 
    come out far enough to allow the next figure. 

B2: Women step into the center, reverence. 
    Men step into the center, reverence.
    Form a left-hand Star. Woman2 (Non-Fred) almost immediately lets go of 
    the star and leads out into a line facing the audience 
    (Man1 aka 'Fred' will be on the left hand side of the line).