Its blocked for me too...
I can give a rough idea, i dont know the science behind it. But when you evaporate the naptha down far enough and blow on it gently, you'll see a white frothy swirl that just kind of clouds it for a min then disappears. I do it every time practally... its pretty coo i suppose
The tragedy of life isn't that it's too short, it's that we take too long to begin it...
-NO TURN UNSTONED-
"Just when I thought I was out, they pulled me back in !!!"
"Compassion becomes real when we recognize our shared humanity" - Pema Chodron