Calling these three sequences "Scottish" is really a bit of a misnomer, since the sources are Alexander Strathy's Elements of the Art of Dancing (Edinburgh, 1822), which is in large part a translation of a French manual by J. H. Goudoux, and an anonymous Scottish manuscript entitled Contre Danses à Paris 1818. All three sequences are certainly French in their steps and style and quite possibly in origin. They probably would not have caused anyone in Paris in that era to bat an eyelash. But technically, they are documented to Scotland, not France, in the late 1810s-early 1820s.
Steps for these sequences are summarized below.
First, an easy one:
1. (Contre Danses à Paris #1)
1b Glissade right, closing behind; assemblé right behind
1b Glissade left, closing behind; assemblé left behind
& repeat (see below)
(count: and ONE, TWO, and THREE, FOUR twice)
Despite being about as basic as one can get, this one actually presented a minor reconstruction problem. The original instruction includes "Et E Contra", which is how the author signifies "and repeat all of that to the other side". Technically, that would mean repeating those two bars starting with a glissade to the left instead of to the right. That's physically possible, but feels unlikely to me in the context of setting sequences in general, so I would simply repeat the same right-left sequence again.
1b Glissade right dessous, jeté right before
1b Glissade left dessous, jeté left before
1b Glissade right dessous, jeté right before
1b Assemblé left before, changement de jambe
(count: and ONE, TWO, and THREE, FOUR, and ONE, TWO, THREE, FOUR)
This is actually the very first sequence for balancer (setting to your partner) described by Strathy, who footnotes it with "I have at present mentioned the most simple movements" and a promise of more sequences to follow later.
This sequence is interesting in that it is distinctly asymmetrical, moving right-left-right before staying in place on the final measure. Facing partners will end up noticeably offset from each other.
Note that all the jeté are front-to-front and that the assemblé in the final measure must be performed with precision so that the last measure does not disintegrate into a pair of changement de jambe.
3. (Strathy and Contre Danses à Paris #4)
1b Glissade right, closing behind; changement de jambe ending in fourth
1b Jeté tendu left before (extending right to second); assemblé right behind
(count: and ONE, TWO, THREE, FOUR twice)
This one is something of an oddity, with the changement de jambe ending in fourth position rather than third or fifth, but the instructions are explicit in both sources.
Note that on the jeté tendu the active foot moves outward and then back to the rear foor, ending up just in front of where the rear foot was before it was extended to second. Strathy does not describe this as a tendu, but that is what ending with the free foot extended implies. The anonymous author of Contre Danses à Paris says it explicitly.
Here are quick summaries of the steps used above. These do not include the full details of the bend and rise of period practice.
Glissade: sliding one foot to the side and closing the other foot to fifth or third position, either behind or in front ("before"). The slide to the side is performed on the upbeat ("and") with the close coming on the downbeat ("ONE"). The original French terms dessous (behind) and dessus (before) are so similar that I've written the closings out in English to avoid confusion.
Jeté: extend one foot out directly to the side (second position raised) then, bringing it either before or behind the other, leap onto it, raising free foot to point straight down, close along the leg. The motion should be "out-and-in". The step is initiated on the upbeat and lands on the downbeat.
Jeté tendu: as the regular jeté, but ending with the free foot extended, generally to second position (though fourth is also possible), rather than tucked in and pointed downward.
Assemblé: extend one foot out directly to the side (second position raised) then bring it in either behind or before while hopping gently into the air, landing in either third or fifth position with weight equally on both feet. Again, this is an "out-and-in" motion with one foot moving, not two feet changing places. It initiates on the upbeat and lands on the downbeat.
Changement de jambe: from third or fifth, jump lightly and switch the positions of the feet. Unlike the assemblé, there is no "out-and-in" motion; the feet travel briefly through first position. Usually this is performed from third/fifth to third/fifth, but as used above, it ends with the feet more widely separated in fourth. It initiates on the upbeat and lands on the downbeat.