Interesting way to see if your gas is adulterated

Well, in some regards, at least. From Popular Mechanics.

"How to tell if you're trying to burn alcohol-bearing gasoline? Here is some simple kitchen-table chemistry. Get a tall, skinny vessel and add a measured amount of ordinary ethylene-glycol-based antifreeze to it. Fill to a level you can check easily, even if it's just a grease pencil mark. The vessel should be about one-third full. Sight to the bottom of the meniscus, not the high point where the liquid wets the wall. Add a similar amount of your suspect gasoline. Cover the top of the vessel and invert it carefully about a dozen times. Do not shake. Allow the mixture to stand for an hour or so to let the bubbles coalesce. Any alcohol--methyl or ethyl--will migrate to the glycol layer on the bottom. If the meniscus stays at the same level, you have pure gasoline. If the meniscus goes up about 10 percent, you have legal oxygenated fuel. If it goes up more than 10 percent, you have adulterated fuel. Be sure to dispose of your gasoline-alcohol-antifreeze highball in some environmentally responsible manner, okay? Check the Saturday Mechanic article in our December issue for details on that."