Now that there’s more stitched it’s probably easier to see the pattern repeat style that I wrote about last week (click on thumbnail below for larger version):

After working with lots of historical graphed strip and border patterns, I can say that the overwhelming majority of the form repeats in three standard ways:

The first one is a straight repeat – no mirroring, and no flipping. It’s common for edging components on larger patterns, like the little acorns on the larger strip below (adapted from V&A T.133-1956), and (no surprise) for totally symmetrical pieces like the multicolor one (adapted from a Siebmacher design from a post 1600 edition that’s not on line):

The second order repeat is a bounce-mirror. There are two vertical centerpoints and the design bounces back and forth between them, but never inverts. Lots of these feature mythical beasts, people or animals – motifs that have a strong up-down identification. Here are two examples from an earlier Siebmacher collection that’s available on line, one with a nifty yale, and one with an abstract heart and flourish.

In the pattern with the yales (heraldic goats) the mirror columns are the center of the flowerpot behind them, and the center of the fountain like object between them. Even this pattern, for all of its complexity is a type 2 – a very wide type 2, with the two mirror columns being the center of the trefoil interlace near the right hand side of the photo, and the center of the heavy stem interlace about a third of the way from the left edge:

The third order repeat can be the most confusing to stitch, but is extremely well represented in historical artifacts. It’s an elaboration on the two mirror bounce repeat in the second example, with alternating iterations flipped north/south for good measure. Although these repeats employ that flip, they’re actually simpler than type 2s, above.

Why am I calling this one simple? Because there’s really only one mirror column: the centermost axis of the flowers. The north facing and south facing flowers are identical. The design may be visually more complex because of the flip, but when stitched there is less variation – less following of unique chart elements – than in a large type 2 pattern.

Here are some more examples of type 3 repeats:

Now to loop around to my current strip, this one is a hybrid:

The entire four leaf grapevine unit repeats as a type 1 – verbatim, with no flipping or mirroring. BUT inside each unit we’ve got type 3 mirroring/flipping. The mirror column (which the mathematically inclined might call an axis of inversion) runs down the center of the unit, and to make things more complex, is skew, rather than a nice bisecting 90-degree line from top to bottom. This is the same symmetry that my current pattern shows.

Both are rather like sideways Z or S units, with a strong diagonal element down the center (in this case the heavy geometric beads, and for the red grapes, the main stem), with items mirrored and flipped to either side of the axis of inversion. The difference between this and red grape pattern is that the individual units in this one are connected. If I chose to, I could have worked the red grapes with every other unit mirrored (in fact, in the original the pattern is shown with a companion center cluster and the clusters I use repeated on each side of it, but mirrored around the center unit). I don’t have that choice in my current strip of black grapes. The repeats are anchored to each other by those stems.

To sum up, there are many ways that repeats are formed in historical patterns, ranging from the simple to the complex. All are legitimate, with sourced examples of employ in historical artifacts (or in my case, pieces stitched from sourced historical designs). Understanding the symmetry helps deconstruct the complexity of the pattern, and (I find) makes working it easier.

So. Why else should we care? Frankly, I haven’t a clue unless you’re a historical embroidery dilettante like me. I find the way that patterns are used, the way that repeats are made, and the way that symmetry is harnessed for general effect to be endless sources of fascination. But I’m a pattern geek. Your mileage may vary.

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