I used to think they called it rip-stop nylon because if it started to rip it would stop. But after years of using sacks and packs and tents and tarps made of rip-stop I concluded that the stuff was just plain unrippable.

I have a camp-kitchen bag into which I once absentmindedly stuffed several loose knives; they cut through here and there, but the cuts never have enlarged by so much as a millimeter. Two years ago I sat huddled all one long night among the dunes of Assateague Island, waiting for my tent, which was popping and snapping like gunshots under 90-mile gusts, to explode into tatters and carry me with it into the cruel sea.

Come dawn I found that blasting sand had half-buried the tent and scoured the sheen from the material, but not one stitch in any seam had even thought about starting. Wanting to do something nice for Eureka, the manufacturer, I went out and bought another tent just like it.

So it was with a tranquil mind that I settled down to sleep in my wildlife observation platform in St. Marys County last Saturday night. The platform is 42 feet up in a tree, but it already had weathered several near-hurricanes, and the canopy was a 10 x 10 Eureka rip-stop tarp that had demonstrated its indestructibility.

If the storm gave any warning I slept through it. I first noticed that something was amiss was when I found myself staring straight at the lightning-lit ground: The tree was bent like a fly rod, and I was lying on what was meant to be the side of the platform, which is wrapped from deck to rail with stout wire fencing.

This lasted less long than it takes to tell, for the tree immediately whipped back the other way, flinging me against the opposite rail. This continued. After some while -- it may have been a little while, but it seemed rather a long one -- the cyclone began to back, and then to box the compass, flinging me now hither, now thither, now yon. Holding on did not serve; the wire cut.

I tried sitting with my back to one railpost and my feet braced against another, but it didn't work and anyway the rain blew up my nose. My life tried to flash before my eyes but the projector kept shorting out whenever my head hit something.

I was, however, able to recall with satisfaction that my insurance man, after reviewing my policies two nights before, had said my widow and orphans would be left very well fixed. He had hinted, in fact, that the best way to put the kids through college would be to do something like get caught up a tree in a thunderstorm. Double indemnity, you know.

I grew weary of waiting for Mother Nature to vouchsafe me quietus, and during a lull tried to take in sail, so as to reduce the strain on the mast. The wind sneaked back and caught me leaning out over the rail reaching for a stay, and the whipping tarp gave me such a slap as last I felt when I tried to steal a kiss from Norma Springer in the sixth grade. I flopped to the deck like spilled pudding, thinking that the wind would at some point tire of playing with that damned immortal rip-stop and carry tree and me away like a parachute in an updraft.

The wind grew stronger yet, so that what had been gusts became the norm and the gusts hammered. I have not asked the weatherman what velocities were recorded because whatever he said would disappoint. When the fencing began to belly and scream I started to sing along, I think, but I couldn't hear what came out.

Then the rip-stop nylon ripped, and did not stop. It carried away like a cannon- cropped flag, and the motion of the tree slacked off to merely sick-making. By dawn I was sufficiently reconciled to being alive to climb down, after counting my bones.

And now I know not only that rip-stop nylon is, hallelujah, not indestructible, but why the Eureka company chose that name. I had guessed that the founder simply labeled his enterprise after the happy thought that led him into it, but in fact eureka is the nearest approximation there is of the noise rip-stop nylon makes when at last it yields.

It is a lovely sound.