| Emery’s Classification and Twills |
Marcy Petrini
July, 2023
I have started planning for HGA’s Spinning and Weaving Week
I have been thinking about Emery’s classification for a few years now, and the more I learn, the more I like its organization. I was originally introduced to it by Donna Sullivan in a workshop on summer and winter, back in the 90’s, but she also discusses it in her book by that name.
A criticism I have heard voiced is that Emery’s classification is not detailed enough. It is true, but that’s not its purpose. My analogy is that of the navigation system in my car. When I drive by a park near me, the navigation system tells me that the area is a park, with green portions, with parking lots, tennis courts, etc. It doesn’t tell me what plants make up the green portion of the area. I don’t criticize the navigation system for the lack of those details.
Irene Emery wrote The Primary Structure of Fabrics in 1966 (Washington, D.C.: The Textile Museum, reprinted with minor edits in 1980). It classifies not only weaving but also every type of fabric. Using this classification, we can look at any fabric and understand its underlying structure.
For me as a weaver, Emery’s classification is a good place to start. For example, twills are considered simple weaves, not because they are necessarily simple in design, but because they are composed of one warp and one weft, which Emery calls elements. The close-up of the shawl below is considered simple, because it has one warp, variegated blues and purples and one weft, light purple. It is a 40-shaft extended pointed twill. I don’t think of this fabric as having a simple design.
If I were weaving a twill with stripes with two wefts, the structure would still be considered simple because the two wefts perform the same function and thus are part of one element.
With this classification, all twills fall in one group, defined as progressive successions of floats in diagonal alignment. This is in contrast to those structures that have intermittent progression of floats (satins) and those that have floats organized in blocks (“Lacey” weaves for example). Both of these are considered simple weaves and so is plain weave.
However, there is no “rule” in Emery’s description that I cannot further subdivide twills.
I like to think of twills in three broad groups: balanced twills, unbalanced twills, and irregular twills sometimes called fancy twills.
In balanced twills, the two sides of the fabric show the same amount of warp and same amount of weft. Each shed activates the same number of shafts, so the twill can be described with a ratio. On four shafts we call them 2/2 twills; with every pick, two shafts are up, two are down. The straight twill below is a good example.
We more shafts, we have more treadling options: The twill below is a 3/2/1/2 straight twill. The rules are the same: with every pick, three shafts are up, two are down, one is up and the last two are down. The sum is the number of shafts used in the structure, in this case eight. Thus, this a balanced twill.
In contrast, in unbalanced twills one side of the fabric is predominantly warp dominant and the other weft dominant. Unbalanced twills can still be described by a ratio. Below are the two sides of a four shaft 3/1 twill: three shafts are up and one remains down with every pick.
In contrast, an irregular twill, also called fancy, cannot be described by a ratio. The steep twill below has fourteen treadling steps; some sheds use one shaft, some use two, and yet others three. (For the drawdown of the steep twill, see the Pictionary© entry on my website).
Where Emery really shines is when we combine structures. The sample below (part of my Covid series, Delta, see December 2021 blog) is a pointed threading, treadled part as a straight twill, part as a reverse straight twill and part as plain weave. But the twills are still twills in Emery’s classification, with added plain weave; the description of the entire fabric is still a simple weave. To analyze it, it would be a good place to start.
Just as we subdivided twills, other classes of structures can be subdivided… tune in Friday, October 6 and learn more!
Happy weaving!
Marcy