It consists of two, Mirror Half reels of three on the Sides of a Longwise set, with the Dancing couple on Opposite Sides for the first Half reel and on their Own sides for the second; from the Supporting Couples point of view, they are performing normal Mirror reels of three.
The whole Inveran reels Figure requires 8 bars; it is named from the Reel, Mrs MacPherson of Inveran, where it appears in bars 1-8.
When, as in this example, it is performed by the first 3 Couples starting from their Original Places, 1st Couple Cross down to start, 1st Lady giving Left shoulder to 3rd Man and 1st Man giving right shoulder to 3rd Lady; at the end of the first Half reel of three, 1st Couple Cross up to start the second Half reel of three, 1st Lady giving Left shoulder to 3rd Lady (in 1st Lady's Place) and 1st Man giving right shoulder to 3rd Man (in 1st Man's Place), all Finishing in their Original Places. The Supporting Couples perform normal Mirror reels of three with one of the Dancing couple for the first Half reel and the other for the second; 2nd Couple Cast up to start, 3rd Couple Dance In and Up and both can Take Nearer hands as in normal Mirror reels of three.
Note that the Dancing couple's paths in the above diagram show the asymmetry (cf. the following diagram for Figures of eight across halfway - lady and man down, albeit with 1st Couple Crossing down from Opposite sides), which is necessary in order to achieve Precedence and avoid a staccato pace when Crossing down or Up. In Inveran reels, the Dancing couple, Starting from Own sides, should Take Right hands when Crossing down and when Crossing up so that the Dancing man can help his Partner to take Precedence and he does not have to mark time in order to let her Pass in front of him.
Note that, because of the asymmetry in the top diagram, the paths have to be reflected about the Centre line; the Dancing couple do not simply follow their Partner's path of the standard form.