Fused plastic

If you've read the novel or seen the 1990s A Room With a View, there's a hilarious scene where an adventurous Lady Novelist confronted with a damp spot of ground tells her timid friend, "Observe my foresight! I never venture forth without my mackintosh squares. At any time, one may have to sit upon damp ground or cold marble."

Now, I have a request from a Literary Adventuress who needs a mackintosh square of her own.

At first, I thought of making up some real mackintosh squares. Authenticity! But rubberized cloth is hard to come by, and plasticized versions usually look like just like cheap tablecloths. Who wants to attempt to sit with any elegance on an little square patterned with pictures of  fried chicken?

I bought some heavy-duty waterproofing spray in the hardware store, but feel a little dubious about whether weatherized fabric will last when folded and shoved into a backpack repeatedly.

So in the short term, I'll make a smaller waterproof pad.

We used to call these sit-upons in Girl Scouts. It's one of the first projects Brownies do, usually with carpet remnants or fleece or something with bubble wrap and duct tape.

This is Step 1 of my little sit-upon project - fusing together plastic grocery bags to make a thick, fabric-like, sewable lining.

It's easy - cut the plastic bags open so that they lie flat, and iron them between two sheets of parchment paper with the iron set to polyester. The plastic is fused one layer at a time, not all at once. It becomes very dense and workable.

What this might miss in true Literary Elegance it will gain in reuse/recycle hippie mom points in the refined airs of Berkeley. One hopes.