What in the World is This? (4)

I took this picture during a trip to India in 1991. Can you guess what it is?

Here's a hint: I took this picture while inside, looking up. And it allowed me to sleep comfortably at night.

Give up? It's a mosquito net.

During that trip many years ago was the first time I had ever seen such a thing. Heck, now you can find them at places like Pier 1 (perhaps for more decorative purposes?) and maybe even at camping stores.

Effective? Yes indeed!