Alcega states that this skirt requires a length of fabric 2 ells long x 2 ells wide, or 168cm (approx 66") long x 168cm (approx 66") wide.
Some mathematics and dimensions
The length of the skirt from waistband to hem is given as "bs" or 1 1/6 ells, which translates as 98cm (approx 38 1/2"). Alcega states that the 'main part' of the skirt is cut along the fold, which seems to indicate that the fabric has been folded in half lengthways, reducing the width to one ell wide, or 84cm (approx 33"). The dimension "mo" given at the waist curve is 5/8 of an ell, or 52.5cm (a bit over 20 1/2"), which x 2 gives a generous waist of 105cm (approx 41 1/3"). The dimensions of the piecings aren't specifically given, but given that we have the fabric width and the lengths of the straight edges it should be fairly easy to work this out.
We know that the fabric is 168cm (approx 66") long, and that the waist to hem dimension is described as 98cm (approx 38 1/2"), so if we deduct this length of skirt from the fabric length, then the bottom straight edge of piece B must be around 70cm (approx 27 1/2").
Er, say what now?
1/3 ell and 2 finger's breadths is given as 31.5cm (a little under 12 1/2"). Could it be referring to the some sort of measurement related to drawing the curve of the waist and hemline?
If the skirt is a true half circle, and we know that the waist is 105cm (approx 41 1/3") long, then we should be able to magic up the radius of the curve through haruspicy, the sweat of our brows and a magic little number called pi. 2 x the waistband given would be a 210cm circle (a bit under 82 3/4"), so if we divide this number by pi (3.142 should suffice) we get a diameter of 66.8cm, which halved would be a radius of 33.4cm (approx 13").
This seems pretty close to the 31.5cm (or 12 1/2") mentioned in the paragraph above, so I wonder if this was Alcega's description of the compass point to the left of the waistband where you start drawing the curve? The slight difference in measurement could be a small error, or it could allow for a seam allowance. (The slightly smaller radius would make a waist measurement less than 105cm, however a seam allowance of a couple of cm would be enough to increase the circumference to the right measurement.)
|Comparative lengths, and the waist curve radius. Click to enlarge.|
We know the folded fabric width is 84cm (approx 38 1/2"), the radius of the waist curve is 31.5cm (or 12 1/2") and final back seam length of the skirt has to be 98cm (approx 38 1/2"). So, 84cm - 31.5cm means that the length of the back as drawn must be 52.5cm (a bit over 20 1/2"), leaving another 45.5cm (approx 18") in length to be added by the piecing at the centre back.
Developing the pattern
The only bit of weirdness in the pattern is the shape of the piecing top left. To my eyes it looks like the curve is heading in the wrong direction if A meets A, and B meets B. So I had a little play in photo editing software and rotated the pieces into position.
|Piece A B rotated into position but not flipped over. Click to enlarge.|
Mmmm. Okay. However, if you flip the piece (either flip it if your fabric does not have a wrong and right side, or use the piece from the other side of the folded fabric if it does) the fit, while not exact, is much improved.
|Piece A B rotated and flipped. Click to elnarge.|
Curious. The other thing noticeable is that if the curve was just drawn heading in the other direction, you could probably squeeze this in without the need to make an even further piecing in B (the little solid line section on B in the original pattern layout). In the accompanying translated text there is mention of the need to take this extra piecing however, so it seems deliberate that the piece was drawn this way. I'm going to follow the layout and description, but flip the pieces when it comes time to sew it together.
I scaled down all the dimensions by roughly one third, to fit the size of my mannequin, and used Alcega's description of the compass point to draw the waist curve and hemline. I grabbed some additional pattern paper and drew the piecings, making sure that the length of the straight edge of A+B = the length of the straight edge A on the main skirt piece, and that total length of the back skirt seam would be the same length as the edge placed on the fold.
|My pattern draft, using scaled down dimensions. Click to enlarge.|
Putting it together
This is a very simple sew.
The main skirt piece is cut on the fold, as is piece B (however the fold is not utilised on piece B, so you have to slice along the fold so you have two separate pieces). Piece A B is then cut on the double layer of fabric. The fabric left over in the top right hand corner of the diagram is used to cut the two small pieces needed to complete piece B where the pattern pieces overlap. There should be a little bit of fabric left over on the straight grain to make a waistband (if not, then cut a waistband from another piece of fabric trimmings). I cut my waistband from two half length pieces, but you can make a simple waistband wherever you find sufficient fabric, so long as it is on the straight grain.
Note: because of the small scale I am working in I had to add a small seam allowance to each piece to be able to construct them, so I used a slightly large piece of fabric to accommodate this.
I began by sewing the piecings B and A B together to form one curved piece with a straight edge that corresponded to the length of edge A, and then sewed these to each side of the main skirt piece. I then closed the centre back seam, leaving an opening large enough to slip it over the head and bust of my mannequin. I then made up the waistband strip, and pleated the large waist allowance to the size of the waistband.
There are no instructions regarding pleats or gathers, but it seems logical to me that you would pleat or gather the fairly generous waist allowance into a waistband to suit the wearer's size. I guess you could re-draw the pattern so that the waist diameter is the actual waist measurement, but the end result would be more like a modern a-line skirt, rather than a full underskirt.
|Finished skirt front. Click to enlarge.|
The calico I am using is a little stiff, so the underskirt hangs in quite an a-line shape. If this was made full scale in a linen then I would imagine the drape would be a little different.
|Finished skirt side. Click to enlarge.|
I drew over the seam lines to highlight the way the pieces are placed at the back rear of the skirt.
|Finished skirt rear. Click to enlarge.|
The skirt back hem is where most of the piecing is evident.
There you have it, a simple underskirt of cloth for a woman. If I have time and energy I might come back and construct the other variants of this for the different types and widths of fabric, because some of the piecings required get very complex (read: cray cray) and that might be worth exploring if I haven't lost my mind by then.
Next up I'll be tacking another skirt, pattern f.58 the "Kirtle of silk for a woman".