I found a cute idea in instructions for a doctor play set: Instead of a box pleat, run elastic through the ends of the mask, and use the same elastic to hold the mask on. Though how one would do that with the loops shown in the picture, I don't know.
Further search showed that the loops are supposed to be hooked over the child's ears. That would stay on my face maybe up to thirty seconds. One picture showed very thick cord elastic!
Ah, useful information! "In doing the math, each mask takes a 10 x 6 piece of fabric for the outside and for the lining. 1/2 yard of each fabric would give you 12 masks."
The pattern is for cutting the cloth up to make a 3-D mask, but holding a tape measure up to my face suggests that ten by six would be about right.
I could put one loop through both hems . . .
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20/20/2020
Pretty soon after writing that, I realized that I was overthinking this. Instead of hunting for a mask pattern that is equivalent to a handkerchief over the face, just tie a handkerchief over my face!
That's at least as good as any mask in the hands of non-medical personell.
Investigation of my pile of hankies showed that I have three real bandanas (made when bandanas were practical rather than the latest fashion), and a linen furoshiki. I make furoshikis in pairs because cutting one leaves a furoshiki-size scrap, so there should be another. I think the other one is in a box or basket somewhere with a forgotten knitting or mending project pinned up in it.
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Then today, I discovered that I *did* have the vast supply of canned cat food I had thought I had when last in the store -- instead of forgetting how long ago I'd bought it, I forgot where I put it. There is plenty to last until Senior Day at Martin's.
(The cat has kidney stones, so we want him to get as many of his calories from wet food as possible, even though the dry food is renal support and the wet food mostly isn't. He detects and detests the flavor of renal support in wet food.)
So instead of going to Tractor Supply tomorrow, I'll go around the south end of the lake, look at the recently-refurbished dam, ride the length of Chinworth Trail, and have a picnic lunch in Tippy Park. I rarely share Tippy Park, and never this early in the season. And if someone else shows up, there are enough tables for a twelve-foot social distance.
Then I can come back past the place where the "The Farm" farm stand will be when the sweeet corn is ripe, just to make it twenty miles.