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While You're Waiting for the Food to Come
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by Eric Muller, Illustrated by Eldon Doty
click on the book cover above or on either cover
liquids drip-up and down. Create a homemade
-Salad oil (olive or sesame oil are best)
-Tall clear glass of cold water, no ice
1) Fill a glass about 3/4 full with cold water.
2) Slowly pour some oil into the glass. Because oil is less
dense than water, the oil will float. Stop pouring when you
have a layer of oil about 1/2 inch or 1 cm thick on the
3) Next, generously sprinkle salt on top of the oil and
watch what happens.
4) Add more salt or any other condiment to see what else
Food for Thought:
Oil is less dense than water, so it floats. Salt is more
dense than both water and oil so it sinks. What makes things
interesting in this trick is that the oil tends to cling to
the salt temporarily. Together, the oil and salt blobs are
denser than water, so they descend to the bottom of the cup.
As the blobs go down, the oil coats and protects the salt
from dissolving. However, after it sinks, the oil soon yanks
free from the salt and floats up again.
Copyright 1996 Eric
While You're Waiting for the Food to Come"
Original copyright of While You're
Waiting for the Food to Come 1995 Eric